Upstream Paper

Organize the Readme and License

.circleci/config.yml

@@ -0,0 +1,50 @@
+version: 2
+jobs:
+  build:
+    working_directory: ~/Akarin-project/Akarin
+    parallelism: 1
+    shell: /bin/bash --login
+    environment:
+      CIRCLE_ARTIFACTS: /tmp/circleci-artifacts
+      CIRCLE_TEST_REPORTS: /tmp/circleci-test-results
+    docker:
+    - image: circleci/build-image:ubuntu-14.04-XXL-upstart-1189-5614f37
+      command: /sbin/init
+    steps:
+    # Machine Setup
+    - checkout
+    # Prepare for artifact
+    - run: mkdir -p $CIRCLE_ARTIFACTS $CIRCLE_TEST_REPORTS
+    - run:
+        working_directory: ~/Akarin-project/Akarin
+        command: sudo update-alternatives --set java /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java; sudo update-alternatives --set javac /usr/lib/jvm/java-8-openjdk-amd64/bin/javac; echo -e "export JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64" >> $BASH_ENV
+    # Dependencies
+    # Restore the dependency cache
+    - restore_cache:
+        keys:
+        # This branch if available
+        - v1-dep-{{ .Branch }}-
+        # Default branch if not
+        - v1-dep-ver/1.12.2-
+        # Any branch if there are none on the default branch - this should be unnecessary if you have your default branch configured correctly
+        - v1-dep-
+    - run: git config --global user.email "circle@circleci.com"
+    - run: git config --global user.name "CircleCI"
+    - run: chmod +x scripts/inst.sh
+    - run: ./scripts/inst.sh --setup --remote
+    # Save dependency cache
+    - save_cache:
+        key: v1-dep-{{ .Branch }}-{{ epoch }}
+        paths:
+        - ~/.m2
+    # Test
+    - run: yes|cp -rf ./akarin-*.jar $CIRCLE_ARTIFACTS
+    # Teardown
+    # Save test results
+    - store_test_results:
+        path: /tmp/circleci-test-results
+    # Save artifacts
+    - store_artifacts:
+        path: /tmp/circleci-artifacts
+    - store_artifacts:
+        path: /tmp/circleci-test-results

LICENSE.md

@@ -4,16 +4,17 @@ As such, Akarin is licensed under the
 [GNU General Public License version 3](licenses/GPL.md); as it inherits it from Paper,
 who in turn inherits it from the original Spigot projects.
 
-Any author who is _not_ listed below should be presumed to have released their work
+Any author who is _not_ listed below should be presumed to have their work released
 under the original [GPL](licenses/GPL.md) license.
 
 In the interest of promoting a better Minecraft platform for everyone, contributors
 may choose to release their code under the more permissive [MIT License](licenses/MIT.md).
 
-The authors listed below have chosen to release their code under that more permissive
+The authors listed below have chosen to release their code under the more permissive
 [MIT License](licenses/MIT.md). Any contributor who wants their name added below
-should submit a pull request to this project to add their name.
+should submit a Pull Request to this project and add their name.
 
 ```text
 Sotr <kira@kira.moe>
+MatrixTunnel <https://github.com/MatrixTunnel>
 ```

README.md

@@ -1,29 +1,33 @@
 # <img src="https://i.loli.net/2018/05/17/5afd869c443ef.png" alt="Akarin Face" align="right">Akarin
-[![Build Status](http://ci.pcd.ac.cn/job/Akarin/badge/icon)](http://ci.ilummc.com/job/Akarin/)
-[![bStats](https://img.shields.io/badge/bStats-Torch-0099ff.svg?style=flat)](https://bstats.org/plugin/bukkit/Torch)
 [![Powered by](https://img.shields.io/badge/Powered_by-Akarin_project-ee6aa7.svg?style=flat)](https://akarin.io)
+[![Chat](https://img.shields.io/badge/chat-on%20discord-7289da.svg)](https://discord.gg/fw2pJAj)
+[![bStats](https://img.shields.io/badge/bStats-Torch-0099ff.svg?style=flat)](https://bstats.org/plugin/bukkit/Torch)
+[![Circle CI](https://circleci.com/gh/Akarin-project/Akarin/tree/master.svg?style=svg)](https://circleci.com/gh/Akarin-project/Akarin/tree/ver/1.12.2)
+
+Akarin is currently **under heavy development** and contributions are welcome!
 
 Introduction
 ---
-> Akarin is a powerful server software form the 'new dimension', formerly known as Torch.
+> Akarin is a powerful server software from the 'new dimension', formerly known as Torch.
 
-As a [Paper](https://github.com/PaperMC/Paper) fork, it supports almost all plugins that [Spigot](https://hub.spigotmc.org/stash/projects/SPIGOT/repos/spigot/browse) can use.
+As a [Paper](https://github.com/PaperMC/Paper) fork, it should support almost all plugins that work on [Spigot](https://hub.spigotmc.org/stash/projects/SPIGOT/repos/spigot/browse).
 
-It has a few key goals:
-* **Open Access** - Make more game mechanism configurable.
-* **Bedrock** - Safety and stable is important for a server. 
-* **Fast** - Simplify the logic and import the multi-thread compute.
+Our project has a few key goals:
 
-Akarin is **under heavy development** yet, contribution is welcome and run a test before putting into production.
+* **Open Access** - Make more game mechanics configurable.
+* **Bedrock** - Make the server more safe and stable. 
+* **Fast** - Simplify the logic and implement multi-threaded computing.
+
+*Issues and Pull Requests will be labeled accordingly*
 
 Get Akarin
 ---
 ### Download
-#### Recommended Sites
-+ [**Jenkins**](http://ci.ilummc.com/job/Akarin/) - *Kudos to [Izzel_Aliz](https://github.com/IzzelAliz)*
-+ [![Circle CI](https://circleci.com/gh/Akarin-project/Akarin/tree/master.svg?style=svg) **Circle CI**](https://circleci.com/gh/Akarin-project/Akarin/tree/master) - Checkout the 'Artifacts' tab of the latest build  *Login required*
+#### Recommended
++ ~~[**Jenkins**](http://ci.ilummc.com/job/Akarin/)~~ - Kudos to [Izzel_Aliz](https://github.com/IzzelAliz)
++ [**Circle CI**](https://circleci.com/gh/Akarin-project/Akarin/tree/ver/1.12.2) - Checkout the 'Artifacts' tab of the latest build
 
-*Contact me via the email below or open an [Issue](https://github.com/Akarin-project/akarin/issues) if you want to add your website here*
+*Open an [Issue](https://github.com/Akarin-project/Akarin/issues) or a [Pull Request](https://github.com/Akarin-project/Akarin/pulls) if you want to add your website here*
 
 ### Build
 #### Requirements
@@ -34,20 +38,23 @@ Get Akarin
 ```sh
 ./scripts/inst.sh --setup --fast
 ```
-*For non-modification compile, add `--fast` option to skip the test is recommended.*
-*Futhermore, if your machine have a insufficient memory, you may add `--remote` option to avoid decompile locally.*
 
-Demonstration servers
+**Notes**
+* You must use `--setup` at least once to deploy necessary dependencies otherwise some imports cannot be organized.
+* For non-modified projects, it is recommended to add the `--fast` option to skip any tests.
+* If your machine has insufficient memory, you may want to add the `--remote` option to avoid decompiling locally.
+
+Demo Servers
 ---
-+ **demo.akarin.io**
+* `demo.akarin.io` (official)
+* `omc.hk` (auth required)
 
-*Contact me via the email below or open an [Issue](https://github.com/Akarin-project/akarin/issues) if you want to add your server here*
+*Open an [Issue](https://github.com/Akarin-project/Akarin/issues) or a [Pull Request](https://github.com/Akarin-project/Akarin/pulls) if you want to add your website here*
 
 Contributing
 ---
-* Feel free to open an [Issue](https://github.com/Akarin-project/akarin/issues) if you have any problem with Akarin.
-* [Pull Request](https://github.com/Akarin-project/akarin/pulls) is welcomed, Akarin use [Mixin](https://github.com/SpongePowered/Mixin) to modify the code, you can checkout `sources` folder to see them. Moreover, add your name to the [LICENSE](https://github.com/Akarin-project/Akarin/blob/master/LICENSE.md) if you want to publish your code under the [MIT License](https://github.com/Akarin-project/Akarin/blob/master/licenses/MIT.md).
-* If you want to join the [Akarin-project](https://github.com/Akarin-project) team, you can send an email to `kira@kira.moe` with your experience and necessary information. Besides, welcome to join our [Discord](https://discord.gg/D3Rsukh) to chat.
-* Note that you must `--setup` at least once to deploy necessary dependency otherwise some imports cannot be organized.
+* Akarin uses [Mixin](https://github.com/SpongePowered/Mixin) to modify the code. You can checkout the `sources` folder to see more. 
+* Add your name to the [LICENSE](https://github.com/Akarin-project/Akarin/blob/master/LICENSE.md) if you want to publish your code under the [MIT License](https://github.com/Akarin-project/Akarin/blob/master/licenses/MIT.md).
+* If you want to join the [Akarin-project](https://github.com/Akarin-project) team, you can [send](mailto://kira@kira.moe) us an email with your experience and necessary information.
 
 ![Akarin project](https://i.loli.net/2018/05/13/5af7fbbfbcddf.png)

circle.yml

@@ -1,16 +0,0 @@
-machine:
-  java:
-    version: openjdk8
-
-dependencies:
-  cache-directories:
-    - "/home/ubuntu/Akarin/work/Paper/work/Minecraft"
-  override:
-    - git config --global user.email "circle@circleci.com"
-    - git config --global user.name "CircleCI"
-    - chmod +x scripts/inst.sh
-    - ./scripts/inst.sh --setup --remote
-
-test:
-  post:
-    - yes|cp -rf ./akarin-1.12.2.jar $CIRCLE_ARTIFACTS

sources/pom.xml

@@ -3,7 +3,7 @@
     <modelVersion>4.0.0</modelVersion>
     <artifactId>akarin</artifactId>
     <packaging>jar</packaging>
-    <version>1.12.2-R0.3-SNAPSHOT</version>
+    <version>1.12.2-R0.4-SNAPSHOT</version>
     <name>Akarin</name>
     <url>https://github.com/Akarin-project/Akarin</url>
 
@@ -73,12 +73,12 @@
         <dependency>
             <groupId>net.minecrell</groupId>
             <artifactId>terminalconsoleappender</artifactId>
-            <version>1.0.0</version>
+            <version>1.1.1</version>
         </dependency>
         <dependency>
             <groupId>net.java.dev.jna</groupId>
             <artifactId>jna</artifactId>
-            <version>4.4.0</version>
+            <version>4.5.2</version>
             <scope>runtime</scope>
         </dependency>
 
@@ -108,6 +108,14 @@
             <version>2.8.1</version>
         </dependency>
         
+        <!-- Paper - Async loggers -->
+        <dependency>
+            <groupId>com.lmax</groupId>
+            <artifactId>disruptor</artifactId>
+            <version>3.4.2</version>
+            <scope>runtime</scope>
+        </dependency>
+
         <!-- testing -->
         <dependency>
             <groupId>junit</groupId>
@@ -126,24 +134,34 @@
         <dependency>
             <groupId>io.akarin</groupId>
             <artifactId>legacylauncher</artifactId>
-            <version>1.23</version>
+            <version>1.26</version>
         </dependency>
         <dependency>
             <groupId>org.spongepowered</groupId>
             <artifactId>mixin</artifactId>
-            <version>0.7.10-SNAPSHOT</version>
+            <version>0.7.11-SNAPSHOT</version>
+        </dependency>
+        <dependency>
+            <groupId>com.googlecode.concurrent-locks</groupId>
+            <artifactId>concurrent-locks</artifactId>
+            <version>1.0.0</version>
+        </dependency>
+        <dependency>
+            <groupId>com.github.ben-manes.caffeine</groupId>
+            <artifactId>caffeine</artifactId>
+            <version>2.6.3-SNAPSHOT</version>
         </dependency>
     </dependencies>
 
     <repositories>
-        <repository>
-            <id>spigotmc-public</id>
-            <url>https://hub.spigotmc.org/nexus/content/groups/public/</url>
-        </repository>
         <repository>
             <id>akarin-repo</id>
             <url>https://raw.githubusercontent.com/Akarin-project/akarin-repo/master/repository</url>
         </repository>
+        <repository>
+            <id>spigotmc-public</id>
+            <url>https://hub.spigotmc.org/nexus/content/groups/public/</url>
+        </repository>
         <repository>
             <id>spongepowered-repo</id>
             <url>https://repo.spongepowered.org/maven/</url>
@@ -269,15 +287,15 @@
                             </transformers>
                             <!-- Akarin - Avoid signature failure -->
                             <filters>
-								<filter>
-									<artifact>*:*</artifact>
-									<excludes>
-										<exclude>META-INF/*.SF</exclude>
-										<exclude>META-INF/*.DSA</exclude>
-										<exclude>META-INF/*.RSA</exclude>
-									</excludes>
-								</filter>
-							</filters>
+                                    <filter>
+									    <artifact>*:*</artifact>
+									    <excludes>
+										    <exclude>META-INF/*.SF</exclude>
+										    <exclude>META-INF/*.DSA</exclude>
+										    <exclude>META-INF/*.RSA</exclude>
+									    </excludes>
+                                </filter>
+                            </filters>
                         </configuration>
                     </execution>
                 </executions>

sources/src/main/java/co/aikar/timings/TimingHandler.java

@@ -1,217 +0,0 @@
-/*
- * This file is licensed under the MIT License (MIT).
- *
- * Copyright (c) 2014 Daniel Ennis <http://aikar.co>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package co.aikar.timings;
-
-import co.aikar.util.LoadingIntMap;
-import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
-import org.bukkit.Bukkit;
-
-import java.util.logging.Level;
-
-/**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add volatile to fields<br>
- * @author cakoyo
- */
-class TimingHandler implements Timing {
-
-    private static int idPool = 1;
-    final int id = idPool++;
-
-    final String name;
-    private final boolean verbose;
-
-    private final Int2ObjectOpenHashMap<TimingData> children = new LoadingIntMap<>(TimingData::new);
-
-    final TimingData record;
-    private final TimingHandler groupHandler;
-
-    private volatile long start = 0; // Akarin - volatile
-    private volatile int timingDepth = 0; // Akarin - volatile
-    private boolean added;
-    private boolean timed;
-    private boolean enabled;
-    private TimingHandler parent;
-
-    TimingHandler(TimingIdentifier id) {
-        if (id.name.startsWith("##")) {
-            verbose = true;
-            this.name = id.name.substring(3);
-        } else {
-            this.name = id.name;
-            verbose = false;
-        }
-
-        this.record = new TimingData(this.id);
-        this.groupHandler = id.groupHandler;
-
-        TimingIdentifier.getGroup(id.group).handlers.add(this);
-        checkEnabled();
-    }
-
-    final void checkEnabled() {
-        enabled = Timings.timingsEnabled && (!verbose || Timings.verboseEnabled);
-    }
-
-    void processTick(boolean violated) {
-        if (timingDepth != 0 || record.getCurTickCount() == 0) {
-            timingDepth = 0;
-            start = 0;
-            return;
-        }
-
-        record.processTick(violated);
-        for (TimingData handler : children.values()) {
-            handler.processTick(violated);
-        }
-    }
-
-    @Override
-    public Timing startTimingIfSync() {
-        if (Bukkit.isPrimaryThread()) {
-            startTiming();
-        }
-        return this;
-    }
-
-    @Override
-    public void stopTimingIfSync() {
-        if (Bukkit.isPrimaryThread()) {
-            stopTiming();
-        }
-    }
-
-    @Override
-    public Timing startTiming() {
-        if (enabled && ++timingDepth == 1) {
-            start = System.nanoTime();
-            parent = TimingsManager.CURRENT;
-            TimingsManager.CURRENT = this;
-        }
-        return this;
-    }
-
-    @Override
-    public void stopTiming() {
-        if (enabled && --timingDepth == 0 && start != 0) {
-            if (!Bukkit.isPrimaryThread()) {
-                Bukkit.getLogger().log(Level.SEVERE, "stopTiming called async for " + name);
-                new Throwable().printStackTrace();
-                start = 0;
-                return;
-            }
-            addDiff(System.nanoTime() - start);
-            start = 0;
-        }
-    }
-
-    @Override
-    public void abort() {
-        if (enabled && timingDepth > 0) {
-            start = 0;
-        }
-    }
-
-    void addDiff(long diff) {
-        if (TimingsManager.CURRENT == this) {
-            TimingsManager.CURRENT = parent;
-            if (parent != null) {
-                parent.children.get(id).add(diff);
-            }
-        }
-        record.add(diff);
-        if (!added) {
-            added = true;
-            timed = true;
-            TimingsManager.HANDLERS.add(this);
-        }
-        if (groupHandler != null) {
-            groupHandler.addDiff(diff);
-            groupHandler.children.get(id).add(diff);
-        }
-    }
-
-    /**
-     * Reset this timer, setting all values to zero.
-     *
-     * @param full
-     */
-    void reset(boolean full) {
-        record.reset();
-        if (full) {
-            timed = false;
-        }
-        start = 0;
-        timingDepth = 0;
-        added = false;
-        children.clear();
-        checkEnabled();
-    }
-
-    @Override
-    public TimingHandler getTimingHandler() {
-        return this;
-    }
-
-    @Override
-    public boolean equals(Object o) {
-        return (this == o);
-    }
-
-    @Override
-    public int hashCode() {
-        return id;
-    }
-
-    /**
-     * This is simply for the Closeable interface so it can be used with
-     * try-with-resources ()
-     */
-    @Override
-    public void close() {
-        stopTimingIfSync();
-    }
-
-    public boolean isSpecial() {
-        return this == TimingsManager.FULL_SERVER_TICK || this == TimingsManager.TIMINGS_TICK;
-    }
-
-    boolean isTimed() {
-        return timed;
-    }
-
-    public boolean isEnabled() {
-        return enabled;
-    }
-
-    TimingData[] cloneChildren() {
-        final TimingData[] clonedChildren = new TimingData[children.size()];
-        int i = 0;
-        for (TimingData child : children.values()) {
-            clonedChildren[i++] = child.clone();
-        }
-        return clonedChildren;
-    }
-}

sources/src/main/java/com/destroystokyo/paper/antixray/PacketPlayOutMapChunkInfo.java

@@ -0,0 +1,85 @@
+package com.destroystokyo.paper.antixray;
+
+import io.netty.buffer.ByteBuf;
+import net.minecraft.server.Chunk;
+import net.minecraft.server.DataPalette;
+import net.minecraft.server.IBlockData;
+import net.minecraft.server.PacketPlayOutMapChunk;
+
+/**
+ * Akarin Changes Note
+ * 1) byte[] -> ByteBuf (compatibility)
+ */
+public class PacketPlayOutMapChunkInfo {
+
+    private final PacketPlayOutMapChunk packetPlayOutMapChunk;
+    private final Chunk chunk;
+    private final int chunkSectionSelector;
+    private ByteBuf data; // Akarin - byte[] -> ByteBuf
+    private final int[] bitsPerValue = new int[16];
+    private final DataPalette[] dataPalettes = new DataPalette[16];
+    private final int[] dataBitsIndexes = new int[16];
+    private final IBlockData[][] predefinedBlockData = new IBlockData[16][];
+
+    public PacketPlayOutMapChunkInfo(PacketPlayOutMapChunk packetPlayOutMapChunk, Chunk chunk, int chunkSectionSelector) {
+        this.packetPlayOutMapChunk = packetPlayOutMapChunk;
+        this.chunk = chunk;
+        this.chunkSectionSelector = chunkSectionSelector;
+    }
+
+    public PacketPlayOutMapChunk getPacketPlayOutMapChunk() {
+        return packetPlayOutMapChunk;
+    }
+
+    public Chunk getChunk() {
+        return chunk;
+    }
+
+    public int getChunkSectionSelector() {
+        return chunkSectionSelector;
+    }
+
+    public byte[] getData() {
+        return data.array(); // Akarin
+    }
+
+    public void setData(ByteBuf data) { // Akarin - byte[] -> ByteBuf
+        this.data = data;
+    }
+
+    public int getBitsPerValue(int chunkSectionIndex) {
+        return bitsPerValue[chunkSectionIndex];
+    }
+
+    public void setBitsPerValue(int chunkSectionIndex, int bitsPerValue) {
+        this.bitsPerValue[chunkSectionIndex] = bitsPerValue;
+    }
+
+    public DataPalette getDataPalette(int chunkSectionIndex) {
+        return dataPalettes[chunkSectionIndex];
+    }
+
+    public void setDataPalette(int chunkSectionIndex, DataPalette dataPalette) {
+        dataPalettes[chunkSectionIndex] = dataPalette;
+    }
+
+    public int getDataBitsIndex(int chunkSectionIndex) {
+        return dataBitsIndexes[chunkSectionIndex];
+    }
+
+    public void setDataBitsIndex(int chunkSectionIndex, int dataBitsIndex) {
+        dataBitsIndexes[chunkSectionIndex] = dataBitsIndex;
+    }
+
+    public IBlockData[] getPredefinedBlockData(int chunkSectionIndex) {
+        return predefinedBlockData[chunkSectionIndex];
+    }
+
+    public void setPredefinedBlockData(int chunkSectionIndex, IBlockData[] predefinedBlockData) {
+        this.predefinedBlockData[chunkSectionIndex] = predefinedBlockData;
+    }
+
+    public boolean isWritten(int chunkSectionIndex) {
+        return bitsPerValue[chunkSectionIndex] != 0;
+    }
+}

sources/src/main/java/io/akarin/api/internal/Akari.java

@@ -4,8 +4,12 @@ import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.Queue;
 import java.util.concurrent.ExecutorCompletionService;
-import java.util.concurrent.Executors;
+import java.util.concurrent.LinkedBlockingQueue;
 import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.locks.ReentrantLock;
+
+import org.apache.commons.lang3.StringUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import com.google.common.collect.Queues;
@@ -13,8 +17,15 @@ import com.google.common.util.concurrent.ThreadFactoryBuilder;
 
 import co.aikar.timings.Timing;
 import co.aikar.timings.Timings;
+import io.akarin.api.internal.Akari.AssignableFactory;
+import io.akarin.api.internal.Akari.TimingSignal;
+import io.akarin.api.internal.utils.ReentrantSpinningLock;
+import io.akarin.api.internal.utils.thread.SuspendableExecutorCompletionService;
+import io.akarin.api.internal.utils.thread.SuspendableThreadPoolExecutor;
 import io.akarin.server.core.AkarinGlobalConfig;
 import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.World;
+import net.minecraft.server.WorldServer;
 
 @SuppressWarnings("restriction")
 public abstract class Akari {
@@ -37,22 +48,65 @@ public abstract class Akari {
         public AssignableThread(Runnable run) {
             super(run);
         }
+        public AssignableThread() {
+            super();
+        }
     }
     
     public static class AssignableFactory implements ThreadFactory {
+        private final String threadName;
+        private int threadNumber;
+        
+        public AssignableFactory(String name) {
+            threadName = name;
+        }
+        
         @Override
         public Thread newThread(Runnable run) {
             Thread thread = new AssignableThread(run);
-            thread.setName("Akarin Parallel Schedule Thread");
+            thread.setName(StringUtils.replaceChars(threadName, "$", String.valueOf(threadNumber++)));
             thread.setPriority(AkarinGlobalConfig.primaryThreadPriority); // Fair
             return thread;
         }
     }
     
-    /**
-     * A common tick pool
-     */
-    public static final ExecutorCompletionService<?> STAGE_TICK = new ExecutorCompletionService<>(Executors.newSingleThreadExecutor(new AssignableFactory()));
+    public static class TimingSignal {
+        public final World tickedWorld;
+        public final boolean isEntities;
+        
+        public TimingSignal(World world, boolean entities) {
+            tickedWorld = world;
+            isEntities = entities;
+        }
+    }
+    
+    public static SuspendableExecutorCompletionService<TimingSignal> STAGE_TICK;
+    
+    static {
+        resizeTickExecutors(3);
+    }
+    
+    public static void resizeTickExecutors(int worlds) {
+        int parallelism;
+        switch (AkarinGlobalConfig.parallelMode) {
+            case -1:
+                return;
+            case 0:
+                parallelism = 2;
+                break;
+            case 1:
+                parallelism = worlds + 1;
+                break;
+            case 2:
+            default:
+                parallelism = worlds * 2;
+                break;
+        }
+        STAGE_TICK = new SuspendableExecutorCompletionService<>(new SuspendableThreadPoolExecutor(parallelism, parallelism,
+                0L, TimeUnit.MILLISECONDS,
+                new LinkedBlockingQueue<Runnable>(),
+                new AssignableFactory("Akarin Parallel Ticking Thread - $")));
+    }
     
     public static boolean isPrimaryThread() {
         return isPrimaryThread(true);
@@ -60,7 +114,7 @@ public abstract class Akari {
     
     public static boolean isPrimaryThread(boolean assign) {
         Thread current = Thread.currentThread();
-        return current == MinecraftServer.getServer().primaryThread || (assign ? current instanceof AssignableThread : false);
+        return current == MinecraftServer.getServer().primaryThread || (assign ? (current.getClass() == AssignableThread.class) : false);
     }
     
     public static final String EMPTY_STRING = "";
@@ -92,9 +146,7 @@ public abstract class Akari {
      */
     public final static Timing worldTiming = getTiming("Akarin - Full World Tick");
     
-    public final static Timing entityCallbackTiming = getTiming("Akarin - Entity Callback");
-    
-    public final static Timing callbackTiming = getTiming("Akarin - Callback");
+    public final static Timing callbackTiming = getTiming("Akarin - Callback Queue");
     
     private static Timing getTiming(String name) {
         try {

sources/src/main/java/io/akarin/api/internal/mixin/IMixinChunk.java

@@ -1,28 +0,0 @@
-package io.akarin.api.internal.mixin;
-
-import java.util.List;
-import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.concurrent.atomic.AtomicInteger;
-
-import javax.annotation.Nullable;
-
-import net.minecraft.server.Chunk;
-import net.minecraft.server.EnumSkyBlock;
-
-public interface IMixinChunk {
-    AtomicInteger getPendingLightUpdates();
-    
-    long getLightUpdateTime();
-    
-    boolean areNeighborsLoaded();
-    
-    @Nullable Chunk getNeighborChunk(int index);
-    
-    CopyOnWriteArrayList<Short> getQueuedLightingUpdates(EnumSkyBlock type);
-    
-    List<Chunk> getNeighbors();
-    
-    void setNeighborChunk(int index, @Nullable Chunk chunk);
-    
-    void setLightUpdateTime(long time);
-}

sources/src/main/java/io/akarin/api/internal/mixin/IMixinLockProvider.java

@@ -1,5 +0,0 @@
-package io.akarin.api.internal.mixin;
-
-public interface IMixinLockProvider {
-    public Object lock();
-}

sources/src/main/java/io/akarin/api/internal/mixin/IMixinWorldServer.java

@@ -1,13 +1,8 @@
 package io.akarin.api.internal.mixin;
 
-import java.util.concurrent.ExecutorService;
-
-import net.minecraft.server.BlockPosition;
-import net.minecraft.server.Chunk;
-import net.minecraft.server.EnumSkyBlock;
+import java.util.Random;
 
 public interface IMixinWorldServer {
-    boolean updateLightAsync(EnumSkyBlock lightType, BlockPosition pos, Chunk chunk);
-    
-    ExecutorService getLightingExecutor();
+    public Object lock();
+    public Random rand();
 }

sources/src/main/java/io/akarin/api/internal/utils/CheckedConcurrentLinkedQueue.java

@@ -33,7 +33,7 @@
  * at http://creativecommons.org/publicdomain/zero/1.0/
  */
 
-package io.akarin.api.internal.collections;
+package io.akarin.api.internal.utils;
 
 import java.util.AbstractQueue;
 import java.util.ArrayList;

sources/src/main/java/io/akarin/api/internal/utils/ReentrantSpinningLock.java

@@ -0,0 +1,102 @@
+package io.akarin.api.internal.utils;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+
+public class ReentrantSpinningLock {
+    /*
+     * Impl Note:
+     * A write lock can reentrant as a read lock, while a
+     * read lock is not allowed to reentrant as a write lock.
+     * READ LOCK IS UNTESTED, USE WITH CATION.
+     */
+    private final AtomicBoolean writeLocked = new AtomicBoolean(false);
+    
+    // --------- Thread local restricted fields ---------
+    private long heldThreadId = 0;
+    private int reentrantLocks = 0;
+    
+    /**
+     * Lock as a typical reentrant write lock
+     */
+    public void lock() {
+        long currentThreadId = Thread.currentThread().getId();
+        if (heldThreadId == currentThreadId) {
+            reentrantLocks++;
+        } else {
+            while (!writeLocked.compareAndSet(false, true)) ; // In case acquire one lock concurrently
+            heldThreadId = currentThreadId;
+        }
+    }
+    
+    public void unlock() {
+        if (reentrantLocks == 0) {
+            heldThreadId = 0;
+            //if (readerThreads.get() == 0 || readerThreads.getAndDecrement() == 1) { // Micro-optimization: this saves one subtract
+                writeLocked.set(false);
+            //}
+        } else {
+            --reentrantLocks;
+        }
+    }
+    
+    private final AtomicInteger readerThreads = new AtomicInteger(0);
+    
+    /**
+     * Lock as a typical reentrant read lock
+     */
+    @Deprecated
+    public void lockWeak() {
+        long currentThreadId = Thread.currentThread().getId();
+        if (heldThreadId == currentThreadId) {
+            reentrantLocks++;
+        } else {
+            if (readerThreads.get() == 0) {
+                while (!writeLocked.compareAndSet(false, true)) ; // Block future write lock
+            }
+            heldThreadId = currentThreadId;
+            readerThreads.getAndIncrement(); // Micro-optimization: this saves one plus
+        }
+    }
+    
+    @Deprecated
+    public void unlockWeak() {
+        if (reentrantLocks == 0) {
+            heldThreadId = 0;
+            writeLocked.set(false);
+        } else {
+            --reentrantLocks;
+        }
+    }
+    
+    // --------- Wrappers to allow typical usages ---------
+    private SpinningWriteLock wrappedWriteLock = new SpinningWriteLock();
+    private SpinningReadLock wrappedReadLock = new SpinningReadLock();
+    
+    public class SpinningWriteLock {
+        public void lock() {
+            lock();
+        }
+        public void unlock() {
+            unlock();
+        }
+    }
+    
+    @Deprecated
+    public class SpinningReadLock {
+        public void lock() {
+            lockWeak();
+        }
+        public void unlock() {
+            unlockWeak();
+        }
+    }
+    
+    public SpinningWriteLock writeLock() {
+        return wrappedWriteLock;
+    }
+    
+    public SpinningReadLock readLock() {
+        return wrappedReadLock;
+    }
+}

sources/src/main/java/io/akarin/api/internal/utils/WrappedCollections.java

@@ -1,4 +1,4 @@
-package io.akarin.api.internal.collections;
+package io.akarin.api.internal.utils;
 
 import java.io.Serializable;
 import java.io.ObjectOutputStream;

sources/src/main/java/io/akarin/api/internal/utils/random/LightRNG.java

@@ -0,0 +1,240 @@
+/*
+Written in 2015 by Sebastiano Vigna (vigna@acm.org)
+
+To the extent possible under law, the author has dedicated all copyright
+and related and neighboring rights to this software to the public domain
+worldwide. This software is distributed without any warranty.
+
+See <http://creativecommons.org/publicdomain/zero/1.0/>. */
+package io.akarin.api.internal.utils.random;
+
+/**
+ * This is a SplittableRandom-style generator, meant to have a tiny state
+ * that permits storing many different generators with low overhead.
+ * It should be rather fast, though no guarantees can be made on all hardware.
+ * <br>
+ * Benchmarking on a Windows laptop with an i7-4700MQ processor running OpenJDK 8
+ * reports generation of 64-bit random long output as 17.8x faster than generating
+ * an equivalent number of random longs with java.util.Random, and generation of
+ * 32-bit random int output as 9.8x faster. Specifically, generating 1 billion longs
+ * took about 1.28 nanoseconds per long (1.277 seconds for the whole group) with
+ * LightRNG, while java.util.Random (which is meant to produce int, to be fair) took
+ * about 22.8 nanoseconds per long (22.797 seconds for the whole group). XorRNG
+ * appears to be occasionally faster on int output than LightRNG, but it isn't clear
+ * why or what causes that (JIT or GC internals, possibly). XorRNG is slightly
+ * slower at generating 64-bit random data, including long and double, but not by
+ * a significant degree (a multiplier between 0.9 and 1.2 times). The only deciding
+ * factor then is state size, where LightRNG is as small as possible for any JVM
+ * object with even a single field: 16 bytes (on a 64-bit JVM; 8-byte objects with
+ * 4 bytes or less of non-static members may be possible on 32-bit JVMs but I can't
+ * find anything confirming that guess).
+ * <br>
+ * So yes, this should be very fast, and with only a single long used per LightRNG,
+ * it is about as memory-efficient as these generators get.
+ * <br>
+ * Written in 2015 by Sebastiano Vigna (vigna@acm.org)
+ * @author Sebastiano Vigna
+ * @author Tommy Ettinger
+ */
+public class LightRNG implements RandomnessSource, StatefulRandomness
+{
+	/** 2 raised to the 53, - 1. */
+    private static final long DOUBLE_MASK = ( 1L << 53 ) - 1;
+    /** 2 raised to the -53. */
+    private static final double NORM_53 = 1. / ( 1L << 53 );
+    /** 2 raised to the 24, -1. */
+    private static final long FLOAT_MASK = ( 1L << 24 ) - 1;
+    /** 2 raised to the -24. */
+    private static final double NORM_24 = 1. / ( 1L << 24 );
+
+	private static final long serialVersionUID = -374415589203474497L;
+
+    public long state; /* The state can be seeded with any value. */
+
+    /** Creates a new generator seeded using Math.random. */
+    public LightRNG() {
+        this((long) Math.floor(Math.random() * Long.MAX_VALUE));
+    }
+
+    public LightRNG( final long seed ) {
+        setSeed(seed);
+    }
+
+    @Override
+    public int next( int bits ) {
+        return (int)( nextLong() & ( 1L << bits ) - 1 );
+    }
+
+    /**
+     * Can return any long, positive or negative, of any size permissible in a 64-bit signed integer.
+     * @return any long, all 64 bits are random
+     */
+    @Override
+    public long nextLong() {
+        long z = ( state += 0x9E3779B97F4A7C15L );
+        z = (z ^ (z >>> 30)) * 0xBF58476D1CE4E5B9L;
+        z = (z ^ (z >>> 27)) * 0x94D049BB133111EBL;
+        return z ^ (z >>> 31);
+    }
+
+    /**
+     * Produces a copy of this RandomnessSource that, if next() and/or nextLong() are called on this object and the
+     * copy, both will generate the same sequence of random numbers from the point copy() was called. This just need to
+     * copy the state so it isn't shared, usually, and produce a new value with the same exact state.
+     *
+     * @return a copy of this RandomnessSource
+     */
+    @Override
+    public RandomnessSource copy() {
+        return new LightRNG(state);
+    }
+
+    /**
+     * Can return any int, positive or negative, of any size permissible in a 32-bit signed integer.
+     * @return any int, all 32 bits are random
+     */
+    public int nextInt() {
+        return (int)nextLong();
+    }
+
+    /**
+     * Exclusive on the upper bound.  The lower bound is 0.
+     * @param bound the upper bound; should be positive
+     * @return a random int less than n and at least equal to 0
+     */
+    public int nextInt( final int bound ) {
+        if ( bound <= 0 ) return 0;
+        int threshold = (0x7fffffff - bound + 1) % bound;
+        for (;;) {
+            int bits = (int)(nextLong() & 0x7fffffff);
+            if (bits >= threshold)
+                return bits % bound;
+        }
+    }
+    /**
+     * Inclusive lower, exclusive upper.
+     * @param lower the lower bound, inclusive, can be positive or negative
+     * @param upper the upper bound, exclusive, should be positive, must be greater than lower
+     * @return a random int at least equal to lower and less than upper
+     */
+    public int nextInt( final int lower, final int upper ) {
+        if ( upper - lower <= 0 ) throw new IllegalArgumentException("Upper bound must be greater than lower bound");
+        return lower + nextInt(upper - lower);
+    }
+
+    /**
+     * Exclusive on the upper bound. The lower bound is 0.
+     * @param bound the upper bound; should be positive
+     * @return a random long less than n
+     */
+    public long nextLong( final long bound ) {
+        if ( bound <= 0 ) return 0;
+        long threshold = (0x7fffffffffffffffL - bound + 1) % bound;
+        for (;;) {
+            long bits = nextLong() & 0x7fffffffffffffffL;
+            if (bits >= threshold)
+                return bits % bound;
+        }
+    }
+
+    /**
+     * Inclusive lower, exclusive upper.
+     * @param lower the lower bound, inclusive, can be positive or negative
+     * @param upper the upper bound, exclusive, should be positive, must be greater than lower
+     * @return a random long at least equal to lower and less than upper
+     */
+    public long nextLong( final long lower, final long upper ) {
+        if ( upper - lower <= 0 )  throw new IllegalArgumentException("Upper bound must be greater than lower bound");
+        return lower + nextLong(upper - lower);
+    }
+    /**
+     * Gets a uniform random double in the range [0.0,1.0)
+     * @return a random double at least equal to 0.0 and less than 1.0
+     */
+    public double nextDouble() {
+        return ( nextLong() & DOUBLE_MASK ) * NORM_53;
+    }
+
+    /**
+     * Gets a uniform random double in the range [0.0,outer) given a positive parameter outer. If outer
+     * is negative, it will be the (exclusive) lower bound and 0.0 will be the (inclusive) upper bound.
+     * @param outer the exclusive outer bound, can be negative
+     * @return a random double between 0.0 (inclusive) and outer (exclusive)
+     */
+    public double nextDouble(final double outer) {
+        return nextDouble() * outer;
+    }
+
+    /**
+     * Gets a uniform random float in the range [0.0,1.0)
+     * @return a random float at least equal to 0.0 and less than 1.0
+     */
+    public float nextFloat() {
+        return (float)( ( nextLong() & FLOAT_MASK ) * NORM_24 );
+    }
+
+    /**
+     * Gets a random value, true or false.
+     * Calls nextLong() once.
+     * @return a random true or false value.
+     */
+    public boolean nextBoolean() {
+        return ( nextLong() & 1 ) != 0L;
+    }
+
+    /**
+     * Given a byte array as a parameter, this will fill the array with random bytes (modifying it
+     * in-place). Calls nextLong() {@code Math.ceil(bytes.length / 8.0)} times.
+     * @param bytes a byte array that will have its contents overwritten with random bytes.
+     */
+    public void nextBytes( final byte[] bytes ) {
+        int i = bytes.length, n = 0;
+        while( i != 0 ) {
+            n = Math.min( i, 8 );
+            for ( long bits = nextLong(); n-- != 0; bits >>= 8 ) bytes[ --i ] = (byte)bits;
+        }
+    }
+
+
+
+    /**
+     * Sets the seed of this generator (which is also the current state).
+     * @param seed the seed to use for this LightRNG, as if it was constructed with this seed.
+     */
+    public void setSeed( final long seed ) {
+        state = seed;
+    }
+    /**
+     * Sets the seed (also the current state) of this generator.
+     * @param seed the seed to use for this LightRNG, as if it was constructed with this seed.
+     */
+    @Override
+    public void setState( final long seed ) {
+        state = seed;
+    }
+    /**
+     * Gets the current state of this generator.
+     * @return the current seed of this LightRNG, changed once per call to nextLong()
+     */
+    @Override
+    public long getState() {
+        return state;
+    }
+
+    /**
+     * Advances or rolls back the LightRNG's state without actually generating numbers. Skip forward
+     * or backward a number of steps specified by advance, where a step is equal to one call to nextInt().
+     * @param advance Number of future generations to skip past. Can be negative to backtrack.
+     * @return the state after skipping.
+     */
+    public long skip(long advance)
+    {
+        return state += 0x9E3779B97F4A7C15L * advance;
+    }
+
+    @Override
+    public String toString() {
+        return "LightRNG (" + state + ")"; // Akarin
+    }
+
+}

sources/src/main/java/io/akarin/api/internal/utils/random/LightRandom.java

@@ -0,0 +1,62 @@
+package io.akarin.api.internal.utils.random;
+
+import java.util.Random;
+
+/**
+ * This is a "fake" LightRandom, backed by the LightRNG.
+ * 
+ * This is useful if you want to quickly replace a Random variable with
+ * LightRNG without breaking every code.
+ */
+public class LightRandom extends Random {
+	public static LightRNG light = new LightRNG(); // LightRNG, static.
+	
+	private static final long serialVersionUID = 1L;
+
+	@Override
+	public int next(int bits) {
+		return light.next(bits);
+	}
+	
+	@Override
+	public void nextBytes(byte[] bytes) {
+		light.nextBytes(bytes);
+	}
+	
+	@Override
+	public int nextInt() {
+		return light.nextInt();
+	}
+	
+	@Override
+	public int nextInt(int n) {
+		return light.nextInt(n);
+	}
+	
+	@Override
+	public long nextLong() {
+		return light.nextLong();
+	}
+	
+	@Override
+	public boolean nextBoolean() {
+		return light.nextBoolean();
+	}
+	
+	@Override
+	public float nextFloat() {
+		return light.nextFloat();
+	}
+	
+	@Override
+	public double nextDouble() {
+		return light.nextDouble();
+	}
+	
+	// Akarin start
+	@Override
+	public void setSeed(long seed) {
+        light.setSeed(seed);
+    }
+	// Akarin end
+}

sources/src/main/java/io/akarin/api/internal/utils/random/RandomnessSource.java

@@ -0,0 +1,40 @@
+package io.akarin.api.internal.utils.random;
+
+import java.io.Serializable;
+
+/**
+ * This interface defines the interactions required of a random number
+ * generator. It is a replacement for Java's built-in Random because for
+ * improved performance.
+ *
+ * @author Eben Howard - http://squidpony.com - howard@squidpony.com
+ */
+public interface RandomnessSource extends Serializable {
+
+    /**
+     * Using this method, any algorithm that might use the built-in Java Random
+     * can interface with this randomness source.
+     *
+     * @param bits the number of bits to be returned
+     * @return the integer containing the appropriate number of bits
+     */
+    int next(int bits);
+
+    /**
+     *
+     * Using this method, any algorithm that needs to efficiently generate more
+     * than 32 bits of random data can interface with this randomness source.
+     *
+     * Get a random long between Long.MIN_VALUE and Long.MAX_VALUE (both inclusive).
+     * @return a random long between Long.MIN_VALUE and Long.MAX_VALUE (both inclusive)
+     */
+    long nextLong();
+
+    /**
+     * Produces a copy of this RandomnessSource that, if next() and/or nextLong() are called on this object and the
+     * copy, both will generate the same sequence of random numbers from the point copy() was called. This just need to
+     * copy the state so it isn't shared, usually, and produce a new value with the same exact state.
+     * @return a copy of this RandomnessSource
+     */
+    RandomnessSource copy();
+}

sources/src/main/java/io/akarin/api/internal/utils/random/StatefulRandomness.java

@@ -0,0 +1,20 @@
+package io.akarin.api.internal.utils.random;
+
+/**
+ * A simple interface for RandomnessSources that have the additional property of a state that can be re-set.
+ * Created by Tommy Ettinger on 9/15/2015.
+ */
+public interface StatefulRandomness extends RandomnessSource {
+    /**
+     * Get the current internal state of the StatefulRandomness as a long.
+     * @return the current internal state of this object.
+     */
+    long getState();
+
+    /**
+     * Set the current internal state of this StatefulRandomness with a long.
+     *
+     * @param state a 64-bit long. You should avoid passing 0, even though some implementations can handle that.
+     */
+    void setState(long state);
+}

sources/src/main/java/io/akarin/api/internal/utils/thread/OpenExecutionException.java

@@ -0,0 +1,7 @@
+package io.akarin.api.internal.utils.thread;
+
+import java.util.concurrent.ExecutionException;
+
+public class OpenExecutionException extends ExecutionException {
+    private static final long serialVersionUID = 7830266012832686185L;
+}

sources/src/main/java/io/akarin/api/internal/utils/thread/SuspendableExecutorCompletionService.java

@@ -0,0 +1,142 @@
+/*
+ * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ *
+ */
+
+/*
+ *
+ *
+ *
+ *
+ *
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+package io.akarin.api.internal.utils.thread;
+
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CompletionService;
+import java.util.concurrent.Future;
+import java.util.concurrent.FutureTask;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.RunnableFuture;
+import java.util.concurrent.TimeUnit;
+
+public class SuspendableExecutorCompletionService<V> implements CompletionService<V> {
+    private final SuspendableThreadPoolExecutor executor;
+    private final BlockingQueue<Future<V>> completionQueue;
+    
+    public void suspend() {
+        executor.suspend();
+    }
+    
+    public void resume() {
+        executor.resume();
+    }
+
+    /**
+     * FutureTask extension to enqueue upon completion
+     */
+    private class QueueingFuture extends FutureTask<Void> {
+        QueueingFuture(RunnableFuture<V> task) {
+            super(task, null);
+            this.task = task;
+        }
+        protected void done() { completionQueue.add(task); }
+        private final Future<V> task;
+    }
+
+    private RunnableFuture<V> newTaskFor(Callable<V> task) {
+        return new FutureTask<V>(task);
+    }
+
+    private RunnableFuture<V> newTaskFor(Runnable task, V result) {
+        return new FutureTask<V>(task, result);
+    }
+
+    /**
+     * Creates an ExecutorCompletionService using the supplied
+     * executor for base task execution and a
+     * {@link LinkedBlockingQueue} as a completion queue.
+     *
+     * @param executor the executor to use
+     * @throws NullPointerException if executor is {@code null}
+     */
+    public SuspendableExecutorCompletionService(SuspendableThreadPoolExecutor executor) {
+        if (executor == null)
+            throw new NullPointerException();
+        this.executor = executor;
+        this.completionQueue = new LinkedBlockingQueue<Future<V>>();
+    }
+
+    /**
+     * Creates an ExecutorCompletionService using the supplied
+     * executor for base task execution and the supplied queue as its
+     * completion queue.
+     *
+     * @param executor the executor to use
+     * @param completionQueue the queue to use as the completion queue
+     *        normally one dedicated for use by this service. This
+     *        queue is treated as unbounded -- failed attempted
+     *        {@code Queue.add} operations for completed tasks cause
+     *        them not to be retrievable.
+     * @throws NullPointerException if executor or completionQueue are {@code null}
+     */
+    public SuspendableExecutorCompletionService(SuspendableThreadPoolExecutor executor,
+                                     BlockingQueue<Future<V>> completionQueue) {
+        if (executor == null || completionQueue == null)
+            throw new NullPointerException();
+        this.executor = executor;
+        this.completionQueue = completionQueue;
+    }
+
+    public Future<V> submit(Callable<V> task) {
+        if (task == null) throw new NullPointerException();
+        RunnableFuture<V> f = newTaskFor(task);
+        executor.execute(new QueueingFuture(f));
+        return f;
+    }
+
+    public Future<V> submit(Runnable task, V result) {
+        if (task == null) throw new NullPointerException();
+        RunnableFuture<V> f = newTaskFor(task, result);
+        executor.execute(new QueueingFuture(f));
+        return f;
+    }
+
+    public Future<V> take() throws InterruptedException {
+        return completionQueue.take();
+    }
+
+    public Future<V> poll() {
+        return completionQueue.poll();
+    }
+
+    public Future<V> poll(long timeout, TimeUnit unit)
+            throws InterruptedException {
+        return completionQueue.poll(timeout, unit);
+    }
+
+}

sources/src/main/java/io/akarin/server/core/AkarinGlobalConfig.java

@@ -160,16 +160,6 @@ public class AkarinGlobalConfig {
         playersPerIOThread = getInt("core.players-per-chunk-io-thread", 50);
     }
     
-    public static boolean silentAsyncTimings;
-    private static void silentAsyncTimings() {
-        silentAsyncTimings = getBoolean("core.always-silent-async-timing", false);
-    }
-    
-    public static boolean legacyWorldTimings;
-    private static void legacyWorldTimings() {
-        legacyWorldTimings = getBoolean("alternative.legacy-world-timings-required", false);
-    }
-    
     public static long timeUpdateInterval;
     private static void timeUpdateInterval() {
         timeUpdateInterval = getSeconds(getString("core.tick-rate.world-time-update-interval", "1s")) * 10;
@@ -201,52 +191,25 @@ public class AkarinGlobalConfig {
     }
     
     public static String messageKick;
-    private static void messageKick() {
-        messageKick = getString("messages.disconnect.kick-player", "Kicked by an operator.");
-    }
-    
     public static String messageBan;
-    private static void messageBan() {
-        messageBan = getString("messages.disconnect.ban-player-name", "You are banned from this server! %s %s");
-    }
-    
     public static String messageBanReason;
-    private static void messageBanReason() {
-        messageBanReason = getString("messages.disconnect.ban-reason", "\nReason: ");
-    }
-    
     public static String messageBanExpires;
-    private static void messageBanExpires() {
-        messageBanExpires = getString("messages.disconnect.ban-expires", "\nYour ban will be removed on ");
-    }
-    
     public static String messageBanIp;
-    private static void messageBanIp() {
-        messageBanIp = getString("messages.disconnect.ban-player-ip", "Your IP address is banned from this server! %s %s");
-    }
-    
     public static String messageDupLogin;
-    private static void messageDupLogin() {
-        messageDupLogin = getString("messages.disconnect.kick-player-duplicate-login", "You logged in from another location");
-    }
-    
     public static String messageJoin;
-    private static void messageJoin() {
-        messageJoin = getString("messages.connect.player-join-server", "§e%s joined the game");
-    }
-    
     public static String messageJoinRenamed;
-    private static void messageJoinRenamed() {
-        messageJoinRenamed = getString("messages.connect.renamed-player-join-server", "§e%s (formerly known as %s) joined the game");
-    }
-    
     public static String messageKickKeepAlive;
-    private static void messagekickKeepAlive() {
-        messageKickKeepAlive = getString("messages.disconnect.kick-player-timeout-keep-alive", "Timed out");
-    }
-    
     public static String messagePlayerQuit;
-    private static void messagePlayerQuit() {
+    private static void messagekickKeepAlive() {
+        messageKick = getString("messages.disconnect.kick-player", "Kicked by an operator.");
+        messageBan = getString("messages.disconnect.ban-player-name", "You are banned from this server! %s %s");
+        messageBanReason = getString("messages.disconnect.ban-reason", "\nReason: ");
+        messageBanExpires = getString("messages.disconnect.ban-expires", "\nYour ban will be removed on ");
+        messageBanIp = getString("messages.disconnect.ban-player-ip", "Your IP address is banned from this server! %s %s");
+        messageDupLogin = getString("messages.disconnect.kick-player-duplicate-login", "You logged in from another location");
+        messageJoin = getString("messages.connect.player-join-server", "§e%s joined the game");
+        messageJoinRenamed = getString("messages.connect.renamed-player-join-server", "§e%s (formerly known as %s) joined the game");
+        messageKickKeepAlive = getString("messages.disconnect.kick-player-timeout-keep-alive", "Timed out");
         messagePlayerQuit = getString("messages.disconnect.player-quit-server", "§e%s left the game");
     }
     
@@ -279,4 +242,19 @@ public class AkarinGlobalConfig {
     private static void sendLightOnlyChunkSection() {
         sendLightOnlyChunkSection = getBoolean("core.send-light-only-chunk-sections", true);
     }
+    
+    public static boolean forceHardcoreDifficulty;
+    private static void forceHardcoreDifficulty() {
+        forceHardcoreDifficulty = getBoolean("alternative.force-difficulty-on-hardcore", true);
+    }
+    
+    public static int fileIOThreads;
+    private static void fileIOThreads() {
+        fileIOThreads = getInt("core.chunk-save-threads", 2);
+    }
+    
+    public static int parallelMode;
+    private static void parallelMode() {
+        parallelMode = getInt("core.parallel-mode", 1);
+    }
 }

sources/src/main/java/io/akarin/server/core/AkarinSlackScheduler.java

@@ -18,11 +18,10 @@ public class AkarinSlackScheduler extends Thread {
         return Singleton.instance;
     }
     
-    public static void boot() {
-        Singleton.instance.setName("Akarin Slack Scheduler Thread");
-        Singleton.instance.setPriority(MIN_PRIORITY);
-        Singleton.instance.setDaemon(true);
-        Singleton.instance.start();
+    public void boot() {
+        setName("Akarin Slack Scheduler Thread");
+        setDaemon(true);
+        start();
         Akari.logger.info("Slack scheduler service started");
     }
     
@@ -41,11 +40,13 @@ public class AkarinSlackScheduler extends Thread {
         MinecraftServer server = MinecraftServer.getServer();
         
         while (server.isRunning()) {
+            long startProcessTiming = System.currentTimeMillis();
             // Send time updates to everyone, it will get the right time from the world the player is in.
             // Time update, from MinecraftServer#D
             if (++updateTime >= AkarinGlobalConfig.timeUpdateInterval) {
                 for (EntityPlayer player : server.getPlayerList().players) {
-                    player.playerConnection.sendPacket(new PacketPlayOutUpdateTime(player.world.getTime(), player.getPlayerTime(), player.world.getGameRules().getBoolean("doDaylightCycle"))); // Add support for per player time
+                    // Add support for per player time
+                    player.playerConnection.sendPacket(new PacketPlayOutUpdateTime(player.world.getTime(), player.getPlayerTime(), player.world.getGameRules().getBoolean("doDaylightCycle")));
                 }
                 updateTime = 0;
             }
@@ -70,12 +71,13 @@ public class AkarinSlackScheduler extends Thread {
                         conn.setPendingPing(true);
                         conn.setLastPing(currentTime);
                         conn.setKeepAliveID(currentTime);
-                        conn.sendPacket(new PacketPlayOutKeepAlive(conn.getKeepAliveID()));
+                        conn.sendPacket(new PacketPlayOutKeepAlive(conn.getKeepAliveID())); // 15s lagg you should stop your server
                     }
                 }
             }
             
             // Force hardcore difficulty, from WorldServer#doTick
+            if (AkarinGlobalConfig.forceHardcoreDifficulty)
             for (WorldServer world : server.worlds) {
                 if (world.getWorldData().isHardcore() && world.getDifficulty() != EnumDifficulty.HARD) {
                     world.getWorldData().setDifficulty(EnumDifficulty.HARD);
@@ -84,11 +86,11 @@ public class AkarinSlackScheduler extends Thread {
             
             // Update player info, from PlayerList#tick
             if (++resendPlayersInfo > AkarinGlobalConfig.playersInfoUpdateInterval) {
-                for (EntityPlayer target : server.getPlayerList().players) {
-                    target.playerConnection.sendPacket(new PacketPlayOutPlayerInfo(PacketPlayOutPlayerInfo.EnumPlayerInfoAction.UPDATE_LATENCY, Iterables.filter(server.getPlayerList().players, new Predicate<EntityPlayer>() {
+                for (EntityPlayer player : server.getPlayerList().players) {
+                    player.playerConnection.sendPacket(new PacketPlayOutPlayerInfo(PacketPlayOutPlayerInfo.EnumPlayerInfoAction.UPDATE_LATENCY, Iterables.filter(server.getPlayerList().players, new Predicate<EntityPlayer>() {
                         @Override
-                        public boolean apply(EntityPlayer input) {
-                            return target.getBukkitEntity().canSee(input.getBukkitEntity());
+                        public boolean apply(EntityPlayer each) {
+                            return player.getBukkitEntity().canSee(each.getBukkitEntity());
                         }
                     })));
                 }
@@ -96,10 +98,9 @@ public class AkarinSlackScheduler extends Thread {
             }
             
             try {
-                Thread.sleep(100);
-            } catch (InterruptedException ex) {
-                Akari.logger.warn("Slack scheduler thread was interrupted unexpectly!");
-                ex.printStackTrace();
+                Thread.sleep(100 - (System.currentTimeMillis() - startProcessTiming));
+            } catch (InterruptedException interrupted) {
+                ;
             }
         }
     }

sources/src/main/java/io/akarin/server/mixin/bootstrap/Watchcat.java

@@ -6,7 +6,6 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import org.bukkit.Bukkit;
-import org.bukkit.craftbukkit.CraftServer;
 import org.spigotmc.RestartCommand;
 import org.spigotmc.WatchdogThread;
 import org.spongepowered.asm.mixin.Final;
@@ -23,6 +22,10 @@ import net.minecraft.server.MinecraftServer;
 public abstract class Watchcat extends Thread {
     @Shadow private static WatchdogThread instance;
     @Shadow private @Final long timeoutTime;
+    @Shadow private @Final long earlyWarningEvery; // Paper - Timeout time for just printing a dump but not restarting
+    @Shadow private @Final long earlyWarningDelay; // Paper
+    @Shadow public static volatile boolean hasStarted; // Paper
+    @Shadow private long lastEarlyWarning; // Paper - Keep track of short dump times to avoid spamming console with short dumps
     @Shadow private @Final boolean restart;
     @Shadow private volatile long lastTick;
     @Shadow private volatile boolean stopping;
@@ -38,48 +41,73 @@ public abstract class Watchcat extends Thread {
     @Overwrite
     public void run() {
         while (!stopping) {
-            //
-            if (lastTick != 0 && System.currentTimeMillis() > lastTick + timeoutTime && !Boolean.getBoolean("disable.watchdog")) { // Paper - Add property to disable
-                Logger log = Bukkit.getServer().getLogger();
-                log.log(Level.SEVERE, "Server has stopped responding!");
-                log.log(Level.SEVERE, "Please report this to https://github.com/Akarin-project/Akarin/issues");
-                log.log(Level.SEVERE, "Be sure to include ALL relevant console errors and Minecraft crash reports");
-                log.log(Level.SEVERE, "Akarin version: " + Bukkit.getServer().getVersion());
-                //
-                if (net.minecraft.server.World.haveWeSilencedAPhysicsCrash) {
-                    log.log(Level.SEVERE, "------------------------------");
-                    log.log(Level.SEVERE, "During the run of the server, a physics stackoverflow was supressed");
-                    log.log(Level.SEVERE, "near " + net.minecraft.server.World.blockLocation);
-                }
-                // Paper start - Warn in watchdog if an excessive velocity was ever set
-                if (CraftServer.excessiveVelEx != null) {
-                    log.log(Level.SEVERE, "------------------------------");
-                    log.log(Level.SEVERE, "During the run of the server, a plugin set an excessive velocity on an entity");
-                    log.log(Level.SEVERE, "This may be the cause of the issue, or it may be entirely unrelated");
-                    log.log(Level.SEVERE, CraftServer.excessiveVelEx.getMessage());
-                    for (StackTraceElement stack : CraftServer.excessiveVelEx.getStackTrace()) {
-                        log.log(Level.SEVERE, "\t\t" + stack);
-                    }
-                }
+            // Paper start
+            long currentTime = System.currentTimeMillis();
+            if ( lastTick != 0 && currentTime > lastTick + earlyWarningEvery && !Boolean.getBoolean("disable.watchdog") )
+            {
+                boolean isLongTimeout = currentTime > lastTick + timeoutTime;
+                // Don't spam early warning dumps
+                if (!isLongTimeout && (earlyWarningEvery <= 0 || !hasStarted || currentTime < lastEarlyWarning + earlyWarningEvery || currentTime < lastTick + earlyWarningDelay))
+                    continue;
+                lastEarlyWarning = currentTime;
                 // Paper end
+                Logger log = Bukkit.getServer().getLogger();
+                // Paper start - Different message when it's a short timeout
+                if (isLongTimeout) {
+                    log.log(Level.SEVERE, "The server has stopped responding!");
+                    log.log(Level.SEVERE, "Please report this to https://github.com/Akarin-project/Akarin/issues"); // Akarin
+                    log.log(Level.SEVERE, "Be sure to include ALL relevant console errors and Minecraft crash reports");
+                    log.log(Level.SEVERE, "Akarin version: " + Bukkit.getServer().getVersion()); // Akarin
+                    //
+                    if (net.minecraft.server.World.haveWeSilencedAPhysicsCrash) {
+                        log.log(Level.SEVERE, "------------------------------");
+                        log.log(Level.SEVERE, "During the run of the server, a physics stackoverflow was supressed");
+                        log.log(Level.SEVERE, "near " + net.minecraft.server.World.blockLocation);
+                    }
+                    // Paper start - Warn in watchdog if an excessive velocity was ever set
+                    if (org.bukkit.craftbukkit.CraftServer.excessiveVelEx != null) {
+                        log.log(Level.SEVERE, "------------------------------");
+                        log.log(Level.SEVERE, "During the run of the server, a plugin set an excessive velocity on an entity");
+                        log.log(Level.SEVERE, "This may be the cause of the issue, or it may be entirely unrelated");
+                        log.log(Level.SEVERE, org.bukkit.craftbukkit.CraftServer.excessiveVelEx.getMessage());
+                        for (StackTraceElement stack : org.bukkit.craftbukkit.CraftServer.excessiveVelEx.getStackTrace()) {
+                            log.log(Level.SEVERE, "\t\t" + stack);
+                        }
+                    }
+                    // Paper end
+                } else {
+                    // log.log(Level.SEVERE, "--- DO NOT REPORT THIS TO PAPER - THIS IS NOT A BUG OR A CRASH ---"); // Akarin
+                    log.log(Level.SEVERE, "The server has not responded for " + (currentTime - lastTick) / 1000 + " seconds! Creating thread dump");
+                }
+                // Paper end - Different message for short timeout
                 log.log(Level.SEVERE, "------------------------------");
                 log.log(Level.SEVERE, "Server thread dump (Look for plugins here before reporting to Akarin!):");
                 dumpThread(ManagementFactory.getThreadMXBean().getThreadInfo(MinecraftServer.getServer().primaryThread.getId(), Integer.MAX_VALUE), log);
                 log.log(Level.SEVERE, "------------------------------");
                 //
-                log.log(Level.SEVERE, "Entire Thread Dump:");
-                ThreadInfo[] threads = ManagementFactory.getThreadMXBean().dumpAllThreads(true, true);
-                for (ThreadInfo thread : threads) {
-                    dumpThread(thread, log);
+                // Paper start - Only print full dump on long timeouts
+                if (isLongTimeout) {
+                    log.log(Level.SEVERE, "Entire Thread Dump:");
+                    ThreadInfo[] threads = ManagementFactory.getThreadMXBean().dumpAllThreads(true, true);
+                    for (ThreadInfo thread : threads) {
+                        dumpThread(thread, log);
+                    }
+                } else {
+                    // log.log(Level.SEVERE, "--- DO NOT REPORT THIS TO PAPER - THIS IS NOT A BUG OR A CRASH ---"); // Akarin
                 }
-                log.log(Level.SEVERE, "------------------------------");
+                    log.log(Level.SEVERE, "------------------------------");
                     
-                if (restart) RestartCommand.restart(); // GC Inlined
-                break;
+                    if ( isLongTimeout )
+                    {
+                    if (restart) {
+                        RestartCommand.restart();
+                    }
+                    break;
+                } // Paper end
             }
             
             try {
-                sleep(9000); // Akarin
+                sleep(1000); // Paper - Reduce check time to every second instead of every ten seconds, more consistent and allows for short timeout
             } catch (InterruptedException ex) {
                 interrupt();
             }

sources/src/main/java/io/akarin/server/mixin/core/MixinAsyncCatcher.java

@@ -7,7 +7,6 @@ import org.spongepowered.asm.mixin.Shadow;
 
 import io.akarin.api.internal.Akari;
 import io.akarin.server.core.AkarinGlobalConfig;
-import net.minecraft.server.PersistentCollection;
 
 @Mixin(value = AsyncCatcher.class, remap = false)
 public abstract class MixinAsyncCatcher {
@@ -23,7 +22,6 @@ public abstract class MixinAsyncCatcher {
             } else {
                 Akari.logger.warn("Asynchronous " + reason + "!");
                 Thread.dumpStack();
-                PersistentCollection.class.getName();
             }
         }
     }

sources/src/main/java/io/akarin/server/mixin/core/MixinChunkSection.java

@@ -11,7 +11,7 @@ import net.minecraft.server.ChunkSection;
 public abstract class MixinChunkSection {
     @Shadow private int nonEmptyBlockCount;
     
-    @Overwrite // PAIL: isEmpty
+    @Overwrite // OBFHELPER: isEmpty
     public boolean a() {
         return AkarinGlobalConfig.sendLightOnlyChunkSection ? false : nonEmptyBlockCount == 0;
     }

sources/src/main/java/io/akarin/server/mixin/core/MixinCommandBan.java

@@ -52,7 +52,7 @@ public abstract class MixinCommandBan {
                     entityplayer.playerConnection.disconnect(hasReason ? message : AkarinGlobalConfig.messageBan);
                 }
                 
-                CommandAbstract.a(sender, (ICommand) this, "commands.ban.success", args[0]); // PAIL: notifyCommandListener
+                CommandAbstract.a(sender, (ICommand) this, "commands.ban.success", args[0]); // OBFHELPER: notifyCommandListener
             }
         } else {
             throw new ExceptionUsage("commands.ban.usage");

sources/src/main/java/io/akarin/server/mixin/core/MixinCommandBanIp.java

@@ -19,7 +19,7 @@ import net.minecraft.server.MinecraftServer;
 
 @Mixin(value = CommandBanIp.class, remap = false)
 public abstract class MixinCommandBanIp {
-    @Overwrite // PAIL: banIp
+    @Overwrite // OBFHELPER: banIp
     protected void a(MinecraftServer server, ICommandListener sender, String args, @Nullable String banReason) {
         // Akarin start - modify message
         boolean hasReason = true;
@@ -31,7 +31,7 @@ public abstract class MixinCommandBanIp {
         IpBanEntry ipbanentry = new IpBanEntry(args, (Date) null, sender.getName(), (Date) null, banReason);
 
         server.getPlayerList().getIPBans().add(ipbanentry);
-        List<EntityPlayer> withIpPlayers = server.getPlayerList().b(args); // PAIL: getPlayersMatchingAddress
+        List<EntityPlayer> withIpPlayers = server.getPlayerList().b(args); // OBFHELPER: getPlayersMatchingAddress
         String[] banPlayerNames = new String[withIpPlayers.size()];
         
         for (int i = 0; i < banPlayerNames.length; i++) {
@@ -41,9 +41,9 @@ public abstract class MixinCommandBanIp {
         }
         
         if (withIpPlayers.isEmpty()) {
-            CommandAbstract.a(sender, (ICommand) this, "commands.banip.success", args); // PAIL: notifyCommandListener
+            CommandAbstract.a(sender, (ICommand) this, "commands.banip.success", args); // OBFHELPER: notifyCommandListener
         } else {
-            CommandAbstract.a(sender, (ICommand) this, "commands.banip.success.players", args, CommandAbstract.a(banPlayerNames)); // PAIL: notifyCommandListener - joinNiceString
+            CommandAbstract.a(sender, (ICommand) this, "commands.banip.success.players", args, CommandAbstract.a(banPlayerNames)); // OBFHELPER: notifyCommandListener - joinNiceString
         }
     }
 }

sources/src/main/java/io/akarin/server/mixin/core/MixinCommandKick.java

@@ -30,11 +30,11 @@ public abstract class MixinCommandKick {
                         message = message + args[i];
                     }
                     target.playerConnection.disconnect(message);
-                    CommandAbstract.a(sender, (ICommand) this, "commands.kick.success.reason", target.getName(), message); // PAIL: notifyCommandListener
+                    CommandAbstract.a(sender, (ICommand) this, "commands.kick.success.reason", target.getName(), message); // OBFHELPER: notifyCommandListener
                     // Akarin end
                 } else {
                     target.playerConnection.disconnect(AkarinGlobalConfig.messageKick); // Akarin
-                    CommandAbstract.a(sender, (ICommand) this, "commands.kick.success", target.getName()); // PAIL: notifyCommandListener
+                    CommandAbstract.a(sender, (ICommand) this, "commands.kick.success", target.getName()); // OBFHELPER: notifyCommandListener
                 }
             }
         } else {

sources/src/main/java/io/akarin/server/mixin/core/MixinFileIOThread.java

@@ -0,0 +1,56 @@
+package io.akarin.server.mixin.core;
+
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+
+import com.destroystokyo.paper.PaperConfig;
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+
+import io.akarin.server.core.AkarinGlobalConfig;
+import net.minecraft.server.FileIOThread;
+import net.minecraft.server.IAsyncChunkSaver;
+
+@Mixin(value = FileIOThread.class, remap = false)
+public abstract class MixinFileIOThread {
+    private final Executor executor = Executors.newFixedThreadPool(AkarinGlobalConfig.fileIOThreads, new ThreadFactoryBuilder().setNameFormat("Akarin File IO Thread - %1$d").setPriority(1).build());
+    private final AtomicInteger queuedChunkCounter = new AtomicInteger(0);
+    
+    @Shadow(aliases = "e") private volatile boolean isAwaitFinish;
+    
+    @Overwrite // OBFHELPER: saveChunk
+    public void a(IAsyncChunkSaver iasyncchunksaver) {
+        queuedChunkCounter.incrementAndGet();
+        executor.execute(() -> writeChunk(iasyncchunksaver));
+    }
+    
+    /**
+     * Process a chunk, re-add to the queue if unsuccessful
+     */
+    private void writeChunk(IAsyncChunkSaver iasyncchunksaver)  {
+        if (!iasyncchunksaver.a()) { // PAIL: WriteNextIO() -> Returns if the write was unsuccessful
+            queuedChunkCounter.decrementAndGet();
+            
+            if (PaperConfig.enableFileIOThreadSleep) {
+                try {
+                    Thread.sleep(isAwaitFinish ? 0L : 2L);
+                } catch (InterruptedException ex) {
+                    ex.printStackTrace();
+                }
+            }
+        } else {
+            writeChunk(iasyncchunksaver);
+        }
+    }
+    
+    @Overwrite // OBFHELPER: waitForFinish
+    public void b() throws InterruptedException {
+        isAwaitFinish = true;
+        while (queuedChunkCounter.get() != 0) Thread.sleep(9L);
+        isAwaitFinish = false;
+    }
+}

sources/src/main/java/io/akarin/server/mixin/core/MixinMinecraftServer.java

@@ -2,9 +2,14 @@ package io.akarin.server.mixin.core;
 
 import java.util.List;
 import java.util.Queue;
+import java.util.concurrent.CancellationException;
+import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorCompletionService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.FutureTask;
+
+import org.apache.commons.lang.WordUtils;
+import org.bukkit.World;
 import org.bukkit.craftbukkit.CraftServer;
 import org.bukkit.craftbukkit.chunkio.ChunkIOExecutor;
 import org.bukkit.event.inventory.InventoryMoveItemEvent;
@@ -21,7 +26,7 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 import co.aikar.timings.MinecraftTimings;
 import io.akarin.api.internal.Akari;
 import io.akarin.api.internal.Akari.AssignableFactory;
-import io.akarin.api.internal.mixin.IMixinLockProvider;
+import io.akarin.api.internal.mixin.IMixinWorldServer;
 import io.akarin.server.core.AkarinGlobalConfig;
 import io.akarin.server.core.AkarinSlackScheduler;
 import net.minecraft.server.BlockPosition;
@@ -40,6 +45,8 @@ import net.minecraft.server.WorldServer;
 @Mixin(value = MinecraftServer.class, remap = false)
 public abstract class MixinMinecraftServer {
     @Shadow @Final public Thread primaryThread;
+    private boolean tickedPrimaryEntities;
+	private int cachedWorldSize;
     
     @Overwrite
     public String getServerModName() {
@@ -54,13 +61,13 @@ public abstract class MixinMinecraftServer {
     private void prerun(CallbackInfo info) {
         primaryThread.setPriority(AkarinGlobalConfig.primaryThreadPriority < Thread.NORM_PRIORITY ? Thread.NORM_PRIORITY :
             (AkarinGlobalConfig.primaryThreadPriority > Thread.MAX_PRIORITY ? 10 : AkarinGlobalConfig.primaryThreadPriority));
+        Akari.resizeTickExecutors((cachedWorldSize = worlds.size()));
         
         for (int i = 0; i < worlds.size(); ++i) {
             WorldServer world = worlds.get(i);
             TileEntityHopper.skipHopperEvents = world.paperConfig.disableHopperMoveEvents || InventoryMoveItemEvent.getHandlerList().getRegisteredListeners().length == 0;
         }
-        AkarinSlackScheduler.boot();
-        
+        AkarinSlackScheduler.get().boot();
     }
     
     @Overwrite
@@ -108,7 +115,7 @@ public abstract class MixinMinecraftServer {
     
     @Overwrite
     protected void l() throws InterruptedException {
-        ExecutorCompletionService<?> executor = new ExecutorCompletionService<>(Executors.newFixedThreadPool(worlds.size(), new AssignableFactory()));
+        ExecutorCompletionService<?> executor = new ExecutorCompletionService<>(Executors.newFixedThreadPool(worlds.size(), new AssignableFactory("Akarin Parallel Terrain Generation Thread - $")));
         
         for (int index = 0; index < worlds.size(); index++) {
             WorldServer world = this.worlds.get(index);
@@ -120,7 +127,11 @@ public abstract class MixinMinecraftServer {
         
         for (WorldServer world : this.worlds) {
             if (world.getWorld().getKeepSpawnInMemory()) executor.take();
-            this.server.getPluginManager().callEvent(new WorldLoadEvent(world.getWorld()));
+        }
+        if (WorldLoadEvent.getHandlerList().getRegisteredListeners().length != 0) {
+            for (WorldServer world : this.worlds) {
+                this.server.getPluginManager().callEvent(new WorldLoadEvent(world.getWorld()));
+            }
         }
         
         enablePluginsPostWorld();
@@ -143,7 +154,11 @@ public abstract class MixinMinecraftServer {
     
     private boolean tickEntities(WorldServer world) {
         try {
+            world.timings.tickEntities.startTiming();
             world.tickEntities();
+            world.timings.tickEntities.stopTiming();
+            world.getTracker().updatePlayers();
+            world.explosionDensityCache.clear(); // Paper - Optimize explosions
         } catch (Throwable throwable) {
             CrashReport crashreport;
             try {
@@ -159,7 +174,9 @@ public abstract class MixinMinecraftServer {
     
     private void tickWorld(WorldServer world) {
         try {
+            world.timings.doTick.startTiming();
             world.doTick();
+            world.timings.doTick.stopTiming();
         } catch (Throwable throwable) {
             CrashReport crashreport;
             try {
@@ -173,8 +190,12 @@ public abstract class MixinMinecraftServer {
     }
     
     @Overwrite
-    public void D() throws InterruptedException {
+    public void D() throws InterruptedException, ExecutionException, CancellationException {
         Runnable runnable;
+        Akari.callbackTiming.startTiming();
+        while ((runnable = Akari.callbackQueue.poll()) != null) runnable.run();
+        Akari.callbackTiming.stopTiming();
+        
         MinecraftTimings.bukkitSchedulerTimer.startTiming();
         this.server.getScheduler().mainThreadHeartbeat(this.ticks);
         MinecraftTimings.bukkitSchedulerTimer.stopTiming();
@@ -195,54 +216,92 @@ public abstract class MixinMinecraftServer {
         ChunkIOExecutor.tick();
         MinecraftTimings.chunkIOTickTimer.stopTiming();
         
-        Akari.worldTiming.startTiming();
-        if (AkarinGlobalConfig.legacyWorldTimings) {
-            for (int i = 0; i < worlds.size(); ++i) {
-                worlds.get(i).timings.tickEntities.startTiming();
-                worlds.get(i).timings.doTick.startTiming();
-            }
-        }
-        Akari.STAGE_TICK.submit(() -> {
-            // Never tick one world concurrently!
-            for (int i = 1; i <= worlds.size(); ++i) {
-                WorldServer world = worlds.get(i < worlds.size() ? i : 0);
-                synchronized (((IMixinLockProvider) world).lock()) {
+        if (cachedWorldSize != worlds.size()) Akari.resizeTickExecutors((cachedWorldSize = worlds.size()));
+        switch (AkarinGlobalConfig.parallelMode) {
+            case 1:
+            case 2:
+            default:
+                // Never tick one world concurrently!
+                for (int i = 0; i < cachedWorldSize; i++) {
+                    // Impl Note:
+                    // Entities ticking: index 1 -> ... -> 0 (parallel)
+                    //   World  ticking: index 0 -> ... (parallel)
+                    int interlace = i + 1;
+                    WorldServer entityWorld = worlds.get(interlace < cachedWorldSize ? interlace : 0);
+                    Akari.STAGE_TICK.submit(() -> {
+                        synchronized (((IMixinWorldServer) entityWorld).lock()) {
+                            tickEntities(entityWorld);
+                        }
+                    }, null/*new TimingSignal(entityWorld, true)*/);
+                    
+                    if (AkarinGlobalConfig.parallelMode != 1) {
+                        int fi = i;
+                        Akari.STAGE_TICK.submit(() -> {
+                            WorldServer world = worlds.get(fi);
+                            synchronized (((IMixinWorldServer) world).lock()) {
+                                tickWorld(world);
+                            }
+                        }, null);
+                    }
+                }
+                
+                if (AkarinGlobalConfig.parallelMode == 1)
+                Akari.STAGE_TICK.submit(() -> {
+                    for (int i = 0; i < cachedWorldSize; i++) {
+                        WorldServer world = worlds.get(i);
+                        synchronized (((IMixinWorldServer) world).lock()) {
+                            tickWorld(world);
+                        }
+                    }
+                }, null);
+                
+                for (int i = (AkarinGlobalConfig.parallelMode == 1 ? cachedWorldSize + 1 : cachedWorldSize * 2); i --> 0 ;) {
+                    Akari.STAGE_TICK.take();
+                }
+                
+                /* for (int i = (AkarinGlobalConfig.parallelMode == 1 ? cachedWorldSize : cachedWorldSize * 2); i --> 0 ;) {
+                    long startTiming = System.nanoTime();
+                    TimingSignal signal = Akari.STAGE_TICK.take().get();
+                    IMixinTimingHandler timing = (IMixinTimingHandler) (signal.isEntities ? signal.tickedWorld.timings.tickEntities : signal.tickedWorld.timings.doTick);
+                    timing.stopTiming(startTiming); // The overlap will be ignored
+                } */
+                
+                break;
+            case 0:
+                Akari.STAGE_TICK.submit(() -> {
+                    for (int i = 1; i <= cachedWorldSize; ++i) {
+                        WorldServer world = worlds.get(i < cachedWorldSize ? i : 0);
+                        synchronized (((IMixinWorldServer) world).lock()) {
+                            tickEntities(world);
+                        }
+                    }
+                }, null);
+                
+                Akari.STAGE_TICK.submit(() -> {
+                    for (int i = 0; i < cachedWorldSize; ++i) {
+                        WorldServer world = worlds.get(i);
+                        synchronized (((IMixinWorldServer) world).lock()) {
+                            tickWorld(world);
+                        }
+                    }
+                }, null);
+                
+                Akari.STAGE_TICK.take();
+                Akari.STAGE_TICK.take();
+                break;
+            case -1:
+                for (int i = 0; i < cachedWorldSize; ++i) {
+                    WorldServer world = worlds.get(i);
+                    tickWorld(world);
                     tickEntities(world);
                 }
-            }
-        }, null);
-        
-        for (int i = 0; i < worlds.size(); ++i) {
-            WorldServer world = worlds.get(i);
-            synchronized (((IMixinLockProvider) world).lock()) {
-                tickWorld(world);
-            }
-        }
-        
-        Akari.entityCallbackTiming.startTiming();
-        Akari.STAGE_TICK.take();
-        Akari.entityCallbackTiming.stopTiming();
-        
-        Akari.worldTiming.stopTiming();
-        if (AkarinGlobalConfig.legacyWorldTimings) {
-            for (int i = 0; i < worlds.size(); ++i) {
-                worlds.get(i).timings.tickEntities.stopTiming();
-                worlds.get(i).timings.doTick.startTiming();
-            }
+                break;
         }
         
         Akari.callbackTiming.startTiming();
         while ((runnable = Akari.callbackQueue.poll()) != null) runnable.run();
         Akari.callbackTiming.stopTiming();
         
-        for (int i = 0; i < worlds.size(); ++i) {
-            WorldServer world = worlds.get(i);
-            tickUnsafeSync(world);
-            
-            world.getTracker().updatePlayers();
-            world.explosionDensityCache.clear(); // Paper - Optimize explosions
-        }
-        
         MinecraftTimings.connectionTimer.startTiming();
         serverConnection().c();
         MinecraftTimings.connectionTimer.stopTiming();
@@ -261,10 +320,4 @@ public abstract class MixinMinecraftServer {
         }
         MinecraftTimings.tickablesTimer.stopTiming();
     }
-    
-    public void tickUnsafeSync(WorldServer world) {
-        world.timings.doChunkMap.startTiming();
-        world.manager.flush();
-        world.timings.doChunkMap.stopTiming();
-    }
 }

sources/src/main/java/io/akarin/server/mixin/core/MixinPlayerList.java

@@ -1,12 +0,0 @@
-package io.akarin.server.mixin.core;
-
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Overwrite;
-
-import net.minecraft.server.PlayerList;
-
-@Mixin(value = PlayerList.class, remap = false)
-public abstract class MixinPlayerList {
-    @Overwrite
-    public void tick() {} // Migrated to slack service
-}

sources/src/main/java/io/akarin/server/mixin/core/MixinTimingHandler.java

@@ -1,5 +1,7 @@
 package io.akarin.server.mixin.core;
 
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
 import java.util.logging.Level;
 
 import org.bukkit.Bukkit;
@@ -7,13 +9,8 @@ import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Overwrite;
 import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
-
 import co.aikar.timings.Timing;
 import io.akarin.api.internal.Akari;
-import io.akarin.api.internal.Akari.AssignableThread;
 import io.akarin.server.core.AkarinGlobalConfig;
 import net.minecraft.server.MinecraftServer;
 
@@ -21,26 +18,18 @@ import net.minecraft.server.MinecraftServer;
 public abstract class MixinTimingHandler {
     @Shadow @Final String name;
     @Shadow private boolean enabled;
-    @Shadow private volatile long start;
-    @Shadow private volatile int timingDepth;
+    @Shadow private long start;
+    @Shadow private int timingDepth;
     
     @Shadow abstract void addDiff(long diff);
     @Shadow public abstract Timing startTiming();
     
     @Overwrite
     public Timing startTimingIfSync() {
-        if (Akari.isPrimaryThread(false)) {
-            startTiming();
-        }
+        startTiming();
         return (Timing) this;
     }
     
-    @SuppressWarnings({ "rawtypes", "unchecked" })
-    @Inject(method = "startTiming", at = @At("HEAD"), cancellable = true)
-    public void onStartTiming(CallbackInfoReturnable ci) {
-        if (!Akari.isPrimaryThread(false)) ci.setReturnValue(this); // Avoid modify any field
-    }
-    
     @Overwrite
     public void stopTimingIfSync() {
         if (Akari.isPrimaryThread(false)) {
@@ -53,20 +42,22 @@ public abstract class MixinTimingHandler {
         stopTiming(false);
     }
     
+    public void stopTiming(long start) {
+        if (enabled) addDiff(System.nanoTime() - start);
+    }
+    
     public void stopTiming(boolean alreadySync) {
-        Thread curThread = Thread.currentThread();
-        if (!enabled || curThread instanceof AssignableThread) return;
-        if (!alreadySync && curThread != MinecraftServer.getServer().primaryThread) {
-            if (AkarinGlobalConfig.silentAsyncTimings) return;
-            
-            Bukkit.getLogger().log(Level.SEVERE, "stopTiming called async for " + name);
-            Thread.dumpStack();
+        if (!enabled || --timingDepth != 0 || start == 0) return;
+        if (!alreadySync) {
+            Thread curThread = Thread.currentThread();
+            if (curThread != MinecraftServer.getServer().primaryThread) {
+                start = 0;
+                return;
+            }
         }
         
-        // Main thread ensured
-        if (--timingDepth == 0 && start != 0) {
-            addDiff(System.nanoTime() - start);
-            start = 0;
-        }
+        // Safety ensured
+        addDiff(System.nanoTime() - start);
+        start = 0;
     }
 }

sources/src/main/java/io/akarin/server/mixin/core/MixinVersionCommand.java

@@ -1,21 +1,58 @@
 package io.akarin.server.mixin.core;
 
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.URL;
 import java.util.Set;
 import org.bukkit.Bukkit;
 import org.bukkit.command.CommandSender;
 import org.bukkit.command.defaults.VersionCommand;
+import org.json.simple.JSONObject;
+import org.json.simple.parser.JSONParser;
+import org.json.simple.parser.ParseException;
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Overwrite;
 import org.spongepowered.asm.mixin.Shadow;
 
+import com.google.common.base.Charsets;
+
 import io.akarin.api.internal.Akari;
 import io.akarin.server.core.AkarinGlobalConfig;
 import net.minecraft.server.MCUtil;
 
 @Mixin(value = VersionCommand.class, remap = false)
 public abstract class MixinVersionCommand {
-    @Shadow private static int getFromRepo(String repo, String hash) { return 0; }
+    @Overwrite
+    private static int getFromRepo(String repo, String hash) {
+        try {
+            HttpURLConnection connection = (HttpURLConnection) new URL("https://api.github.com/repos/" + repo + "/compare/ver/1.12.2..." + hash).openConnection();
+            connection.connect();
+            if (connection.getResponseCode() == HttpURLConnection.HTTP_NOT_FOUND) return -2; // Unknown commit
+            try (
+                    BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), Charsets.UTF_8))
+            ) {
+                JSONObject obj = (JSONObject) new JSONParser().parse(reader);
+                String status = (String) obj.get("status");
+                switch (status) {
+                    case "identical":
+                        return 0;
+                    case "behind":
+                        return ((Number) obj.get("behind_by")).intValue();
+                    default:
+                        return -1;
+                }
+            } catch (ParseException | NumberFormatException e) {
+                e.printStackTrace();
+                return -1;
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+            return -1;
+        }
+    }
     
     /**
      * Match current version with repository and calculate the distance
@@ -59,6 +96,9 @@ public abstract class MixinVersionCommand {
         // This should be lying in 'obtainVersion' method, but bump for faster returning
         if (customVersion) return;
         
+        synchronized (versionWaiters) {
+            versionWaiters.add(sender);
+        }
         if (versionObtaining) return;
         // The volatile guarantees the safety between different threads.
         // Remembers that we are still on main thread now,
@@ -100,8 +140,6 @@ public abstract class MixinVersionCommand {
         // We post all things because a custom version is rare (expiring is not rare),
         // and we'd better post this task as early as we can, since it's a will (horrible destiny).
         MCUtil.scheduleAsyncTask(() -> {
-            // This should be lying in 'sendVersion' method, but comes here for relax main thread
-            versionWaiters.add(sender);
             sender.sendMessage("Checking version, please wait...");
             
             String version = Akari.getServerVersion();
@@ -140,9 +178,11 @@ public abstract class MixinVersionCommand {
         versionMessage = message;
         hasVersion = true;
         
-        for (CommandSender sender : versionWaiters) {
-            sender.sendMessage(versionMessage);
+        synchronized (versionWaiters) {
+            for (CommandSender sender : versionWaiters) {
+                sender.sendMessage(versionMessage);
+            }
+            versionWaiters.clear();
         }
-        versionWaiters.clear();
     }
 }

sources/src/main/java/io/akarin/server/mixin/core/MixinWorld.java

@@ -5,6 +5,7 @@ import java.util.List;
 import javax.annotation.Nullable;
 
 import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
 import org.spongepowered.asm.mixin.Shadow;
 
 import net.minecraft.server.AxisAlignedBB;
@@ -21,11 +22,12 @@ public abstract class MixinWorld {
     /**
      * Returns true if there are no solid, live entities in the specified AxisAlignedBB, excluding the given entity
      */
-    public boolean a(AxisAlignedBB box, @Nullable Entity target) { // PAIL: checkNoEntityCollision
+    @Overwrite
+    public boolean a(AxisAlignedBB box, @Nullable Entity target) { // OBFHELPER: checkNoEntityCollision
         List<Entity> list = this.getEntities(null, box);
         
         for (Entity each : list) {
-            if (!each.dead && each.i && each != target && (target == null || !each.x(target))) { // PAIL: preventEntitySpawning - isRidingSameEntity
+            if (!each.dead && each.i && each != target && (target == null || !each.x(target))) { // OBFHELPER: preventEntitySpawning - isRidingSameEntity
                 return false;
             }
         }

sources/src/main/java/io/akarin/server/mixin/core/MixinWorldManager.java

@@ -0,0 +1,27 @@
+package io.akarin.server.mixin.core;
+
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+
+import net.minecraft.server.Entity;
+import net.minecraft.server.EntityPlayer;
+import net.minecraft.server.WorldManager;
+import net.minecraft.server.WorldServer;
+
+@Mixin(value = WorldManager.class, remap = false)
+public abstract class MixinWorldManager {
+    @Shadow @Final private WorldServer world;
+    
+    @Overwrite
+    public void a(Entity entity) {
+        this.world.getTracker().entriesLock.writeLock().lock(); // Akarin
+        this.world.getTracker().track(entity);
+        this.world.getTracker().entriesLock.writeLock().unlock(); // Akarin
+        
+        if (entity instanceof EntityPlayer) {
+            this.world.worldProvider.a((EntityPlayer) entity);
+        }
+    }
+}

sources/src/main/java/io/akarin/server/mixin/core/MixinWorldServer.java

@@ -1,24 +1,37 @@
 package io.akarin.server.mixin.core;
 
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Redirect;
+import java.util.Random;
 
-import io.akarin.api.internal.mixin.IMixinLockProvider;
+import org.apache.logging.log4j.LogManager;
+import org.spongepowered.asm.mixin.Mixin;
+import io.akarin.api.internal.mixin.IMixinWorldServer;
 import net.minecraft.server.WorldServer;
 
 @Mixin(value = WorldServer.class, remap = false)
-public abstract class MixinWorldServer implements IMixinLockProvider {
-    @Redirect(method = "doTick", at = @At(
-            value = "INVOKE",
-            target = "net/minecraft/server/PlayerChunkMap.flush()V"
-    ))
-    public void onFlush() {} // Migrated to main thread
-    
+public abstract class MixinWorldServer implements IMixinWorldServer {
     private final Object tickLock = new Object();
 
     @Override
     public Object lock() {
         return tickLock;
     }
+    
+    private final Random sharedRandom = new io.akarin.api.internal.utils.random.LightRandom() {
+        private static final long serialVersionUID = 1L;
+        private boolean locked = false;
+        @Override
+        public synchronized void setSeed(long seed) {
+            if (locked) {
+                LogManager.getLogger().error("Ignoring setSeed on Entity.SHARED_RANDOM", new Throwable());
+            } else {
+                super.setSeed(seed);
+                locked = true;
+            }
+        }
+    };
+    
+    @Override
+    public Random rand() {
+        return sharedRandom;
+    }
 }

sources/src/main/java/io/akarin/server/mixin/core/MonsterEggGuardian.java

@@ -1,23 +0,0 @@
-package io.akarin.server.mixin.core;
-
-import org.spongepowered.asm.lib.Opcodes;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Redirect;
-
-import io.akarin.server.core.AkarinGlobalConfig;
-import net.minecraft.server.Block;
-import net.minecraft.server.Blocks;
-import net.minecraft.server.ItemMonsterEgg;
-
-@Mixin(value = ItemMonsterEgg.class, remap = false)
-public abstract class MonsterEggGuardian {
-    @Redirect(method = "a", at = @At(
-            value = "FIELD",
-            target = "net/minecraft/server/Blocks.MOB_SPAWNER:Lnet/minecraft/server/Block;",
-            opcode = Opcodes.GETSTATIC
-    ))
-    private boolean configurable(Block target) {
-        return target == Blocks.MOB_SPAWNER && AkarinGlobalConfig.allowSpawnerModify;
-    }
-}

sources/src/main/java/io/akarin/server/mixin/cps/MixinChunk.java

@@ -1,130 +0,0 @@
-/*
- * This file is part of Sponge, licensed under the MIT License (MIT).
- *
- * Copyright (c) SpongePowered <https://www.spongepowered.org>
- * Copyright (c) contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package io.akarin.server.mixin.cps;
-
-import java.util.List;
-import javax.annotation.Nullable;
-
-import org.spongepowered.asm.mixin.Final;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import com.google.common.collect.Lists;
-
-import io.akarin.api.internal.mixin.IMixinChunk;
-import net.minecraft.server.BlockPosition;
-import net.minecraft.server.Chunk;
-import net.minecraft.server.EnumDirection;
-import net.minecraft.server.MCUtil;
-import net.minecraft.server.World;
-
-@Mixin(value = Chunk.class, remap = false)
-public abstract class MixinChunk implements IMixinChunk {
-    private Chunk[] neighborChunks = new Chunk[4];
-    private static final EnumDirection[] CARDINAL_DIRECTIONS = new EnumDirection[] {EnumDirection.NORTH, EnumDirection.SOUTH, EnumDirection.EAST, EnumDirection.WEST};
-    
-    @Shadow @Final public World world;
-    @Shadow @Final public int locX;
-    @Shadow @Final public int locZ;
-    
-    @Override
-    public Chunk getNeighborChunk(int index) {
-        return this.neighborChunks[index];
-    }
-    
-    @Override
-    public void setNeighborChunk(int index, @Nullable Chunk chunk) {
-        this.neighborChunks[index] = chunk;
-    }
-    
-    @Override
-    public List<Chunk> getNeighbors() {
-        List<Chunk> neighborList = Lists.newArrayList();
-        for (Chunk neighbor : this.neighborChunks) {
-            if (neighbor != null) {
-                neighborList.add(neighbor);
-            }
-        }
-        return neighborList;
-    }
-    
-    @Override
-    public boolean areNeighborsLoaded() {
-        for (int i = 0; i < 4; i++) {
-            if (this.neighborChunks[i] == null) {
-                return false;
-            }
-        }
-        return true;
-    }
-    
-    private static int directionToIndex(EnumDirection direction) {
-        switch (direction) {
-            case NORTH:
-                return 0;
-            case SOUTH:
-                return 1;
-            case EAST:
-                return 2;
-            case WEST:
-                return 3;
-            default:
-                throw new IllegalArgumentException("Unexpected direction");
-        }
-    }
-    
-    @Inject(method = "addEntities", at = @At("RETURN"))
-    public void onLoadReturn(CallbackInfo ci) {
-        BlockPosition origin = new BlockPosition(locX, 0, locZ);
-        for (EnumDirection direction : CARDINAL_DIRECTIONS) {
-            BlockPosition shift = origin.shift(direction);
-            Chunk neighbor = MCUtil.getLoadedChunkWithoutMarkingActive(world.getChunkProvider(), shift.getX(), shift.getZ());
-            if (neighbor != null) {
-                int neighborIndex = directionToIndex(direction);
-                int oppositeNeighborIndex = directionToIndex(direction.opposite());
-                this.setNeighborChunk(neighborIndex, neighbor);
-                ((IMixinChunk) neighbor).setNeighborChunk(oppositeNeighborIndex, (Chunk) (Object) this);
-            }
-        }
-    }
-    
-    @Inject(method = "removeEntities", at = @At("RETURN"))
-    public void onUnload(CallbackInfo ci) {
-        BlockPosition origin = new BlockPosition(locX, 0, locZ);
-        for (EnumDirection direction : CARDINAL_DIRECTIONS) {
-            BlockPosition shift = origin.shift(direction);
-            Chunk neighbor = MCUtil.getLoadedChunkWithoutMarkingActive(world.getChunkProvider(), shift.getX(), shift.getZ());
-            if (neighbor != null) {
-                int neighborIndex = directionToIndex(direction);
-                int oppositeNeighborIndex = directionToIndex(direction.opposite());
-                this.setNeighborChunk(neighborIndex, null);
-                ((IMixinChunk) neighbor).setNeighborChunk(oppositeNeighborIndex, null);
-            }
-        }
-    }
-}

sources/src/main/java/io/akarin/server/mixin/cps/MixinChunkProviderServer.java

@@ -40,6 +40,7 @@ public abstract class MixinChunkProviderServer {
             long unloadAfter = world.paperConfig.delayChunkUnloadsBy;
             SlackActivityAccountant activityAccountant = world.getMinecraftServer().slackActivityAccountant;
             activityAccountant.startActivity(0.5);
+            
             ObjectIterator<Entry<Chunk>> it = chunks.long2ObjectEntrySet().fastIterator();
             int remainingChunks = chunks.size();
             int targetSize = Math.min(remainingChunks - 100,  (int) (remainingChunks * UNLOAD_QUEUE_RESIZE_FACTOR)); // Paper - Make more aggressive
@@ -47,27 +48,23 @@ public abstract class MixinChunkProviderServer {
             while (it.hasNext()) {
                 Entry<Chunk> entry = it.next();
                 Chunk chunk = entry.getValue();
-                if (chunk == null) continue;
                 
-                if (chunk.isUnloading()) {
+                if (chunk != null && chunk.isUnloading()) {
                     if (chunk.scheduledForUnload != null) {
-                        if (now - chunk.scheduledForUnload > unloadAfter) {
-                            chunk.scheduledForUnload = null;
-                        } else continue;
+                        if (now - chunk.scheduledForUnload <= unloadAfter) continue;
                     }
                     
-                    if (!unloadChunk(chunk, true)) { // Event cancelled
-                        // If a plugin cancelled it, we shouldn't trying unload it for a while
-                        chunk.setShouldUnload(false);
-                        continue;
+                    if (unloadChunk(chunk, true)) {
+                        it.remove();
                     }
+                    chunk.setShouldUnload(false);
+                    chunk.scheduledForUnload = null;
                     
-                    it.remove();
-                    if (--remainingChunks <= targetSize || activityAccountant.activityTimeIsExhausted()) break; // more slack since the target size not work as intended
+                    if (--remainingChunks <= targetSize && activityAccountant.activityTimeIsExhausted()) break;
                 }
             }
             activityAccountant.endActivity();
-            this.chunkLoader.b(); // PAIL: chunkTick
+            this.chunkLoader.b(); // OBFHELPER: chunkTick
         }
         return false;
     }

sources/src/main/java/io/akarin/server/mixin/lighting/MixinChunk.java

@@ -1,640 +0,0 @@
-/*
- * This file is part of Sponge, licensed under the MIT License (MIT).
- *
- * Copyright (c) SpongePowered <https://www.spongepowered.org>
- * Copyright (c) contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package io.akarin.server.mixin.lighting;
-
-import java.util.Collections;
-import java.util.List;
-import java.util.concurrent.ConcurrentLinkedQueue;
-import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.RejectedExecutionException;
-import java.util.concurrent.atomic.AtomicInteger;
-
-import javax.annotation.Nullable;
-
-import org.spongepowered.asm.mixin.Final;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.injection.Inject;
-import org.spongepowered.asm.mixin.injection.Redirect;
-import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
-
-import com.google.common.collect.Lists;
-
-import io.akarin.api.internal.Akari;
-import io.akarin.api.internal.mixin.IMixinChunk;
-import io.akarin.api.internal.mixin.IMixinWorldServer;
-import net.minecraft.server.BlockPosition;
-import net.minecraft.server.Blocks;
-import net.minecraft.server.Chunk;
-import net.minecraft.server.ChunkSection;
-import net.minecraft.server.EnumDirection;
-import net.minecraft.server.EnumSkyBlock;
-import net.minecraft.server.IBlockData;
-import net.minecraft.server.MCUtil;
-import net.minecraft.server.TileEntity;
-import net.minecraft.server.World;
-import net.minecraft.server.BlockPosition.MutableBlockPosition;
-
-@Mixin(value = Chunk.class, remap = false, priority = 1001)
-public abstract class MixinChunk implements IMixinChunk {
-    
-    // Keeps track of block positions in this chunk currently queued for sky light update
-    private CopyOnWriteArrayList<Short> queuedSkyLightingUpdates = new CopyOnWriteArrayList<>();
-    // Keeps track of block positions in this chunk currently queued for block light update
-    private CopyOnWriteArrayList<Short> queuedBlockLightingUpdates = new CopyOnWriteArrayList<>();
-    private AtomicInteger pendingLightUpdates = new AtomicInteger();
-    private long lightUpdateTime;
-    private ExecutorService lightExecutorService;
-    
-    @Shadow(aliases = "m") private boolean isGapLightingUpdated;
-    @Shadow(aliases = "r") private boolean ticked;
-    @Shadow @Final private ChunkSection[] sections;
-    @Shadow @Final public int locX;
-    @Shadow @Final public int locZ;
-    @Shadow @Final public World world;
-    @Shadow @Final public int[] heightMap;
-    /** Which columns need their skylightMaps updated. */
-    @Shadow(aliases = "i") @Final private boolean[] updateSkylightColumns;
-    /** Queue containing the BlockPosition of tile entities queued for creation */
-    @Shadow(aliases = "y") @Final private ConcurrentLinkedQueue<BlockPosition> tileEntityPosQueue;
-    /** Boolean value indicating if the terrain is populated. */
-    @Shadow(aliases = "done") private boolean isTerrainPopulated;
-    @Shadow(aliases = "lit") private boolean isLightPopulated;
-    /** Lowest value in the heightmap. */
-    @Shadow(aliases = "v") private int heightMapMinimum;
-    
-    @Shadow(aliases = "b") public abstract int getHeightValue(int x, int z);
-    @Shadow(aliases = "g") @Nullable public abstract TileEntity createNewTileEntity(BlockPosition pos);
-    @Shadow(aliases = "a") @Nullable public abstract TileEntity getTileEntity(BlockPosition pos, Chunk.EnumTileEntityState state);
-    @Shadow @Final public abstract IBlockData getBlockData(BlockPosition pos);
-    @Shadow @Final public abstract IBlockData getBlockData(int x, int y, int z);
-    @Shadow public abstract boolean isUnloading();
-    /** Checks the height of a block next to a sky-visible block and schedules a lighting update as necessary */
-    @Shadow(aliases = "b") public abstract void checkSkylightNeighborHeight(int x, int z, int maxValue);
-    @Shadow(aliases = "a") public abstract void updateSkylightNeighborHeight(int x, int z, int startY, int endY);
-    @Shadow(aliases = "z") public abstract void setSkylightUpdated();
-    @Shadow(aliases = "g") public abstract int getTopFilledSegment();
-    @Shadow public abstract void markDirty();
-    
-    @Inject(method = "<init>", at = @At("RETURN"))
-    public void onConstruct(World worldIn, int x, int z, CallbackInfo ci) {
-        lightExecutorService = ((IMixinWorldServer) worldIn).getLightingExecutor();
-    }
-    
-    @Override
-    public AtomicInteger getPendingLightUpdates() {
-        return this.pendingLightUpdates;
-    }
-    
-    @Override
-    public long getLightUpdateTime() {
-        return this.lightUpdateTime;
-    }
-    
-    @Override
-    public void setLightUpdateTime(long time) {
-        this.lightUpdateTime = time;
-    }
-    
-    @Inject(method = "b(Z)V", at = @At("HEAD"), cancellable = true)
-    private void onTickHead(boolean skipRecheckGaps, CallbackInfo ci) {
-        final List<Chunk> neighbors = this.getSurroundingChunks();
-        if (this.isGapLightingUpdated && this.world.worldProvider.m() && !skipRecheckGaps && !neighbors.isEmpty()) { // PAIL: hasSkyLight
-            lightExecutorService.execute(() -> {
-                this.recheckGapsAsync(neighbors);
-            });
-            this.isGapLightingUpdated = false;
-        }
-        
-        this.ticked = true;
-        
-        if (!this.isLightPopulated && this.isTerrainPopulated && !neighbors.isEmpty()) {
-            lightExecutorService.execute(() -> {
-                this.checkLightAsync(neighbors);
-            });
-            // set to true to avoid requeuing the same task when not finished
-            this.isLightPopulated = true;
-        }
-        
-        while (!this.tileEntityPosQueue.isEmpty()) {
-            BlockPosition blockpos = this.tileEntityPosQueue.poll();
-            
-            if (this.getTileEntity(blockpos, Chunk.EnumTileEntityState.CHECK) == null && this.getBlockData(blockpos).getBlock().isTileEntity()) { // PAIL: getTileEntity
-                TileEntity tileentity = this.createNewTileEntity(blockpos);
-                this.world.setTileEntity(blockpos, tileentity);
-                this.world.b(blockpos, blockpos); // PAIL: markBlockRangeForRenderUpdate
-            }
-        }
-        ci.cancel();
-    }
-    
-    @Redirect(method = "b(III)V", at = @At(value = "INVOKE", target = "net/minecraft/server/World.getHighestBlockYAt(Lnet/minecraft/server/BlockPosition;)Lnet/minecraft/server/BlockPosition;"))
-    private BlockPosition onCheckSkylightGetHeight(World world, BlockPosition pos) {
-        final Chunk chunk = this.getLightChunk(pos.getX() >> 4, pos.getZ() >> 4, null);
-        if (chunk == null) {
-            return BlockPosition.ZERO;
-        }
-        
-        return new BlockPosition(pos.getX(), chunk.b(pos.getX() & 15, pos.getZ() & 15), pos.getZ()); // PAIL: getHeightValue
-    }
-    
-    @Redirect(method = "a(IIII)V", at = @At(value = "INVOKE", target = "net/minecraft/server/World.areChunksLoaded(Lnet/minecraft/server/BlockPosition;I)Z"))
-    private boolean onAreaLoadedSkyLightNeighbor(World world, BlockPosition pos, int radius) {
-        return this.isAreaLoaded();
-    }
-    
-    @Redirect(method = "a(IIII)V", at = @At(value = "INVOKE", target = "net/minecraft/server/World.c(Lnet/minecraft/server/EnumSkyBlock;Lnet/minecraft/server/BlockPosition;)Z"))
-    private boolean onCheckLightForSkylightNeighbor(World world, EnumSkyBlock enumSkyBlock, BlockPosition pos) {
-        return this.checkWorldLightFor(enumSkyBlock, pos);
-    }
-    
-    /**
-     * Rechecks chunk gaps async.
-     * 
-     * @param neighbors A thread-safe list of surrounding neighbor chunks
-     */
-    private void recheckGapsAsync(List<Chunk> neighbors) {
-        for (int i = 0; i < 16; ++i) {
-            for (int j = 0; j < 16; ++j) {
-                if (this.updateSkylightColumns[i + j * 16]) {
-                    this.updateSkylightColumns[i + j * 16] = false;
-                    int k = this.getHeightValue(i, j);
-                    int l = this.locX * 16 + i;
-                    int i1 = this.locZ * 16 + j;
-                    int j1 = Integer.MAX_VALUE;
-                    
-                    for (EnumDirection enumfacing : EnumDirection.EnumDirectionLimit.HORIZONTAL) {
-                        final Chunk chunk = this.getLightChunk((l + enumfacing.getAdjacentX()) >> 4, (i1 + enumfacing.getAdjacentZ()) >> 4, neighbors);
-                        if (chunk == null || chunk.isUnloading()) {
-                            continue;
-                        }
-                        j1 = Math.min(j1, chunk.w()); // PAIL: getLowestHeight
-                    }
-                    
-                    this.checkSkylightNeighborHeight(l, i1, j1);
-                    
-                    for (EnumDirection enumfacing1 : EnumDirection.EnumDirectionLimit.HORIZONTAL) {
-                        this.checkSkylightNeighborHeight(l + enumfacing1.getAdjacentX(), i1 + enumfacing1.getAdjacentZ(), k);
-                    }
-                }
-            }
-            
-            // this.isGapLightingUpdated = false;
-        }
-    }
-    
-    @Redirect(method = "n()V", at = @At(value = "INVOKE", target = "net/minecraft/server/World.getType(Lnet/minecraft/server/BlockPosition;)Lnet/minecraft/server/IBlockData;"))
-    private IBlockData onRelightChecksGetBlockData(World world, BlockPosition pos) {
-        Chunk chunk = MCUtil.getLoadedChunkWithoutMarkingActive(world.getChunkProvider(), pos.getX() >> 4, pos.getZ() >> 4);
-        
-        final IMixinChunk spongeChunk = (IMixinChunk) chunk;
-        if (chunk == null || chunk.isUnloading() || !spongeChunk.areNeighborsLoaded()) {
-            return Blocks.AIR.getBlockData();
-        }
-        
-        return chunk.getBlockData(pos);
-    }
-    
-    @Redirect(method = "n()V", at = @At(value = "INVOKE", target = "net/minecraft/server/World.w(Lnet/minecraft/server/BlockPosition;)Z"))
-    private boolean onRelightChecksCheckLight(World world, BlockPosition pos) {
-        return this.checkWorldLight(pos);
-    }
-    
-    // Avoids grabbing chunk async during light check
-    @Redirect(method = "e(II)Z", at = @At(value = "INVOKE", target = "net/minecraft/server/World.w(Lnet/minecraft/server/BlockPosition;)Z"))
-    private boolean onCheckLightWorld(World world, BlockPosition pos) {
-        return this.checkWorldLight(pos);
-    }
-    
-    @Inject(method = "o()V", at = @At("HEAD"), cancellable = true)
-    private void checkLightHead(CallbackInfo ci) {
-        if (this.world.getMinecraftServer().isStopped() || lightExecutorService.isShutdown()) {
-            return;
-        }
-        
-        if (this.isUnloading()) {
-            return;
-        }
-        final List<Chunk> neighborChunks = this.getSurroundingChunks();
-        if (neighborChunks.isEmpty()) {
-            this.isLightPopulated = false;
-            return;
-        }
-        
-        if (Akari.isPrimaryThread(false)) {
-            try {
-                lightExecutorService.execute(() -> {
-                    this.checkLightAsync(neighborChunks);
-                });
-            } catch (RejectedExecutionException ex) {
-                // This could happen if ServerHangWatchdog kills the server
-                // between the start of the method and the execute() call.
-                if (!this.world.getMinecraftServer().isStopped() && !lightExecutorService.isShutdown()) {
-                    throw ex;
-                }
-            }
-        } else {
-            this.checkLightAsync(neighborChunks);
-        }
-        ci.cancel();
-    }
-    
-    /**
-     * Checks light async.
-     * 
-     * @param neighbors A thread-safe list of surrounding neighbor chunks
-     */
-    private void checkLightAsync(List<Chunk> neighbors) {
-        this.isTerrainPopulated = true;
-        this.isLightPopulated = true;
-        BlockPosition blockpos = new BlockPosition(this.locX << 4, 0, this.locZ << 4);
-        
-        if (this.world.worldProvider.m()) { // PAIL: hasSkyLight
-            reCheckLight:
-            
-            for (int i = 0; i < 16; ++i) {
-                for (int j = 0; j < 16; ++j) {
-                    if (!this.checkLightAsync(i, j, neighbors)) {
-                        this.isLightPopulated = false;
-                        break reCheckLight;
-                    }
-                }
-            }
-            
-            if (this.isLightPopulated) {
-                for (EnumDirection enumfacing : EnumDirection.EnumDirectionLimit.HORIZONTAL) {
-                    int k = enumfacing.c() == EnumDirection.EnumAxisDirection.POSITIVE ? 16 : 1; // PAIL: getAxisDirection
-                    final BlockPosition pos = blockpos.shift(enumfacing, k);
-                    final Chunk chunk = this.getLightChunk(pos.getX() >> 4, pos.getZ() >> 4, neighbors);
-                    if (chunk == null) {
-                        continue;
-                    }
-                    chunk.checkLightSide(enumfacing.opposite());
-                }
-                
-                this.setSkylightUpdated();
-            }
-        }
-    }
-    
-    /**
-     * Checks light async.
-     * 
-     * @param x The x position of chunk
-     * @param z The z position of chunk
-     * @param neighbors A thread-safe list of surrounding neighbor chunks
-     * @return True if light update was successful, false if not
-     */
-    private boolean checkLightAsync(int x, int z, List<Chunk> neighbors) {
-        int i = this.getTopFilledSegment();
-        boolean flag = false;
-        boolean flag1 = false;
-        MutableBlockPosition blockpos$mutableblockpos = new MutableBlockPosition((this.locX << 4) + x, 0, (this.locZ << 4) + z);
-        
-        for (int j = i + 16 - 1; j > this.world.getSeaLevel() || j > 0 && !flag1; --j) {
-            blockpos$mutableblockpos.setValues(blockpos$mutableblockpos.getX(), j, blockpos$mutableblockpos.getZ());
-            int k = this.getBlockData(blockpos$mutableblockpos).c(); // PAIL: getLightOpacity
-            
-            if (k == 255 && blockpos$mutableblockpos.getY() < this.world.getSeaLevel()) {
-                flag1 = true;
-            }
-            
-            if (!flag && k > 0) {
-                flag = true;
-            } else if (flag && k == 0 && !this.checkWorldLight(blockpos$mutableblockpos, neighbors)) {
-                return false;
-            }
-        }
-        
-        for (int l = blockpos$mutableblockpos.getY(); l > 0; --l) {
-            blockpos$mutableblockpos.setValues(blockpos$mutableblockpos.getX(), l, blockpos$mutableblockpos.getZ());
-            
-            if (this.getBlockData(blockpos$mutableblockpos).d() > 0) { // getLightValue
-                this.checkWorldLight(blockpos$mutableblockpos, neighbors);
-            }
-        }
-        
-        return true;
-    }
-    
-    /**
-     * Thread-safe method to retrieve a chunk during async light updates.
-     * 
-     * @param chunkX The x position of chunk.
-     * @param chunkZ The z position of chunk.
-     * @param neighbors A thread-safe list of surrounding neighbor chunks
-     * @return The chunk if available, null if not
-     */
-    private Chunk getLightChunk(int chunkX, int chunkZ, List<Chunk> neighbors) {
-        final Chunk currentChunk = (Chunk) (Object) this;
-        if (currentChunk.a(chunkX, chunkZ)) { // PAIL: isAtLocation
-            if (currentChunk.isUnloading()) {
-                return null;
-            }
-            return currentChunk;
-        }
-        if (neighbors == null) {
-            neighbors = this.getSurroundingChunks();
-            if (neighbors.isEmpty()) {
-                return null;
-            }
-        }
-        for (Chunk neighbor : neighbors) {
-            if (neighbor.a(chunkX, chunkZ)) { // PAIL: isAtLocation
-                if (neighbor.isUnloading()) {
-                    return null;
-                }
-                return neighbor;
-            }
-        }
-
-        return null;
-    }
-    
-    /**
-     * Checks if surrounding chunks are loaded thread-safe.
-     * 
-     * @return True if surrounded chunks are loaded, false if not
-     */
-    private boolean isAreaLoaded() {
-        if (!this.areNeighborsLoaded()) {
-            return false;
-        }
-        
-        // add diagonal chunks
-        final Chunk southEastChunk = ((IMixinChunk) this.getNeighborChunk(0)).getNeighborChunk(2);
-        if (southEastChunk == null) {
-            return false;
-        }
-        
-        final Chunk southWestChunk = ((IMixinChunk) this.getNeighborChunk(0)).getNeighborChunk(3);
-        if (southWestChunk == null) {
-            return false;
-        }
-        
-        final Chunk northEastChunk = ((IMixinChunk) this.getNeighborChunk(1)).getNeighborChunk(2);
-        if (northEastChunk == null) {
-            return false;
-        }
-        
-        final Chunk northWestChunk = ((IMixinChunk) this.getNeighborChunk(1)).getNeighborChunk(3);
-        if (northWestChunk == null) {
-            return false;
-        }
-        
-        return true;
-    }
-    
-    /**
-     * Gets surrounding chunks thread-safe.
-     * 
-     * @return The list of surrounding chunks, empty list if not loaded
-     */
-    private List<Chunk> getSurroundingChunks() {
-        if (!this.areNeighborsLoaded()) {
-            return Collections.emptyList();
-        }
-        
-        // add diagonal chunks
-        final Chunk southEastChunk = ((IMixinChunk) this.getNeighborChunk(0)).getNeighborChunk(2);
-        if (southEastChunk == null) {
-            return Collections.emptyList();
-        }
-        
-        final Chunk southWestChunk = ((IMixinChunk) this.getNeighborChunk(0)).getNeighborChunk(3);
-        if (southWestChunk == null) {
-            return Collections.emptyList();
-        }
-        
-        final Chunk northEastChunk = ((IMixinChunk) this.getNeighborChunk(1)).getNeighborChunk(2);
-        if (northEastChunk == null) {
-            return Collections.emptyList();
-        }
-        
-        final Chunk northWestChunk = ((IMixinChunk) this.getNeighborChunk(1)).getNeighborChunk(3);
-        if (northWestChunk == null) {
-            return Collections.emptyList();
-        }
-        
-        List<Chunk> chunkList = Lists.newArrayList();
-        chunkList = this.getNeighbors();
-        chunkList.add(southEastChunk);
-        chunkList.add(southWestChunk);
-        chunkList.add(northEastChunk);
-        chunkList.add(northWestChunk);
-        return chunkList;
-    }
-    
-    @Inject(method = "c(III)V", at = @At("HEAD"), cancellable = true)
-    private void onRelightBlock(int x, int y, int z, CallbackInfo ci) {
-        lightExecutorService.execute(() -> {
-            this.relightBlockAsync(x, y, z);
-        });
-        ci.cancel();
-    }
-    
-    /**
-     * Relight's a block async.
-     * 
-     * @param x The x position
-     * @param y The y position
-     * @param z The z position
-     */
-    private void relightBlockAsync(int x, int y, int z) {
-        int i = this.heightMap[z << 4 | x] & 255;
-        int j = i;
-        
-        if (y > i) {
-            j = y;
-        }
-        
-        while (j > 0 && this.getBlockData(x, j - 1, z).c() == 0) { // PAIL: getLightOpacity
-            --j;
-        }
-        
-        if (j != i) {
-            this.markBlocksDirtyVerticalAsync(x + this.locX * 16, z + this.locZ * 16, j, i);
-            this.heightMap[z << 4 | x] = j;
-            int k = this.locX * 16 + x;
-            int l = this.locZ * 16 + z;
-            
-            if (this.world.worldProvider.m()) { // PAIL: hasSkyLight
-                if (j < i) {
-                    for (int j1 = j; j1 < i; ++j1) {
-                        ChunkSection extendedblockstorage2 = this.sections[j1 >> 4];
-                        
-                        if (extendedblockstorage2 != Chunk.EMPTY_CHUNK_SECTION) {
-                            extendedblockstorage2.a(x, j1 & 15, z, 15); // PAIL: setSkyLight
-                            // this.world.m(new BlockPosition((this.locX << 4) + x, j1, (this.locZ << 4) + z)); // PAIL: notifyLightSet - client side
-                        }
-                    }
-                } else {
-                    for (int i1 = i; i1 < j; ++i1) {
-                        ChunkSection extendedblockstorage = this.sections[i1 >> 4];
-                        
-                        if (extendedblockstorage != Chunk.EMPTY_CHUNK_SECTION) {
-                            extendedblockstorage.a(x, i1 & 15, z, 0); // PAIL: setSkyLight
-                            // this.world.m(new BlockPosition((this.locX << 4) + x, i1, (this.locZ << 4) + z)); // PAIL: notifyLightSet - client side
-                        }
-                    }
-                }
-                
-                int k1 = 15;
-                
-                while (j > 0 && k1 > 0) {
-                    --j;
-                    int i2 = this.getBlockData(x, j, z).c();
-                    
-                    if (i2 == 0) {
-                        i2 = 1;
-                    }
-                    
-                    k1 -= i2;
-                    
-                    if (k1 < 0) {
-                        k1 = 0;
-                    }
-                    
-                    ChunkSection extendedblockstorage1 = this.sections[j >> 4];
-                    
-                    if (extendedblockstorage1 != Chunk.EMPTY_CHUNK_SECTION) {
-                        extendedblockstorage1.a(x, j & 15, z, k1); // PAIL: setSkyLight
-                    }
-                }
-            }
-            
-            int l1 = this.heightMap[z << 4 | x];
-            int j2 = i;
-            int k2 = l1;
-            
-            if (l1 < i) {
-                j2 = l1;
-                k2 = i;
-            }
-            
-            if (l1 < this.heightMapMinimum) {
-                this.heightMapMinimum = l1;
-            }
-            
-            if (this.world.worldProvider.m()) { // PAIL: hasSkyLight
-                for (EnumDirection enumfacing : EnumDirection.EnumDirectionLimit.HORIZONTAL) {
-                    this.updateSkylightNeighborHeight(k + enumfacing.getAdjacentX(), l + enumfacing.getAdjacentZ(), j2, k2); // PAIL: updateSkylightNeighborHeight
-                }
-                
-                this.updateSkylightNeighborHeight(k, l, j2, k2);
-            }
-            
-            this.markDirty();
-        }
-    }
-    
-    /**
-     * Marks a vertical line of blocks as dirty async.
-     * Instead of calling world directly, we pass chunk safely for async light method.
-     * 
-     * @param x1
-     * @param z1
-     * @param x2
-     * @param z2
-     */
-    private void markBlocksDirtyVerticalAsync(int x1, int z1, int x2, int z2) {
-        if (x2 > z2) {
-            int i = z2;
-            z2 = x2;
-            x2 = i;
-        }
-        
-        if (this.world.worldProvider.m()) { // PAIL: hasSkyLight
-            for (int j = x2; j <= z2; ++j) {
-                final BlockPosition pos = new BlockPosition(x1, j, z1);
-                final Chunk chunk = this.getLightChunk(pos.getX() >> 4, pos.getZ() >> 4, null);
-                if (chunk == null) {
-                    continue;
-                }
-                ((IMixinWorldServer) this.world).updateLightAsync(EnumSkyBlock.SKY, new BlockPosition(x1, j, z1), chunk);
-            }
-        }
-        
-        this.world.b(x1, x2, z1, x1, z2, z1); // PAIL: markBlockRangeForRenderUpdate
-    }
-    
-    /**
-     * Checks world light thread-safe.
-     * 
-     * @param lightType The type of light to check
-     * @param pos The block position
-     * @return True if light update was successful, false if not
-     */
-    private boolean checkWorldLightFor(EnumSkyBlock lightType, BlockPosition pos) {
-        final Chunk chunk = this.getLightChunk(pos.getX() >> 4, pos.getZ() >> 4, null);
-        if (chunk == null) {
-            return false;
-        }
-        
-        return ((IMixinWorldServer) this.world).updateLightAsync(lightType, pos, chunk);
-    }
-    
-    private boolean checkWorldLight(BlockPosition pos) {
-        return this.checkWorldLight(pos, null);
-    }
-    
-    /**
-     * Checks world light async.
-     * 
-     * @param pos The block position
-     * @param neighbors A thread-safe list of surrounding neighbor chunks
-     * @return True if light update was successful, false if not
-     */
-    private boolean checkWorldLight(BlockPosition pos, List<Chunk> neighbors) {
-        boolean flag = false;
-        final Chunk chunk = this.getLightChunk(pos.getX() >> 4, pos.getZ() >> 4, neighbors);
-        if (chunk == null) {
-            return false;
-        }
-        
-        if (this.world.worldProvider.m()) { // PAIL: hasSkyLight
-            flag |= ((IMixinWorldServer) this.world).updateLightAsync(EnumSkyBlock.SKY, pos, chunk);
-        }
-        
-        flag = flag | ((IMixinWorldServer) this.world).updateLightAsync(EnumSkyBlock.BLOCK, pos, chunk);
-        return flag;
-    }
-    
-    /**
-     * Gets the list of block positions currently queued for lighting updates.
-     * 
-     * @param type The light type
-     * @return The list of queued block positions, empty if none
-     */
-    @Override
-    public CopyOnWriteArrayList<Short> getQueuedLightingUpdates(EnumSkyBlock type) {
-        if (type == EnumSkyBlock.SKY) {
-            return this.queuedSkyLightingUpdates;
-        }
-        return this.queuedBlockLightingUpdates;
-    }
-}

sources/src/main/java/io/akarin/server/mixin/lighting/MixinChunkProviderServer.java

@@ -1,51 +0,0 @@
-/*
- * This file is part of Sponge, licensed under the MIT License (MIT).
- *
- * Copyright (c) SpongePowered <https://www.spongepowered.org>
- * Copyright (c) contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package io.akarin.server.mixin.lighting;
-
-import org.spongepowered.asm.mixin.Final;
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.injection.At;
-import org.spongepowered.asm.mixin.Shadow;
-import org.spongepowered.asm.mixin.injection.Redirect;
-
-import io.akarin.api.internal.mixin.IMixinChunk;
-import net.minecraft.server.ChunkProviderServer;
-import net.minecraft.server.WorldServer;
-
-@Mixin(value = ChunkProviderServer.class, remap = false, priority = 1001)
-public abstract class MixinChunkProviderServer {
-    @Shadow @Final public WorldServer world;
-
-    @Redirect(method = "unloadChunks", at = @At(
-            value = "INVOKE",
-            target = "Lnet/minecraft/server/Chunk;isUnloading()Z"
-    ))
-    public boolean shouldUnload(IMixinChunk chunk) {
-        if (chunk.getPendingLightUpdates().get() > 0 || this.world.getTime() - chunk.getLightUpdateTime() < 20) {
-            return false;
-        }
-        return true;
-    }
-}

sources/src/main/java/io/akarin/server/mixin/lighting/MixinWorld.java

@@ -1,46 +0,0 @@
-/*
- * This file is part of Sponge, licensed under the MIT License (MIT).
- *
- * Copyright (c) SpongePowered <https://www.spongepowered.org>
- * Copyright (c) contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package io.akarin.server.mixin.lighting;
-
-import org.spongepowered.asm.mixin.Mixin;
-import org.spongepowered.asm.mixin.Shadow;
-
-import net.minecraft.server.BlockPosition;
-import net.minecraft.server.Chunk;
-import net.minecraft.server.EnumSkyBlock;
-import net.minecraft.server.IChunkProvider;
-import net.minecraft.server.MinecraftServer;
-import net.minecraft.server.World;
-
-@Mixin(value = World.class, remap = false, priority = 1001)
-public abstract class MixinWorld {
-    @Shadow protected IChunkProvider chunkProvider;
-    @Shadow int[] J; // PAIL: lightUpdateBlockList
-    
-    @Shadow(aliases = "c") public abstract boolean checkLightFor(EnumSkyBlock lightType, BlockPosition pos);
-    @Shadow public abstract MinecraftServer getMinecraftServer();
-    @Shadow public abstract boolean areChunksLoaded(BlockPosition center, int radius, boolean allowEmpty);
-    @Shadow public abstract Chunk getChunkIfLoaded(int x, int z);
-}

sources/src/main/java/io/akarin/server/mixin/lighting/MixinWorldServer.java

@@ -1,374 +0,0 @@
-/*
- * This file is part of Sponge, licensed under the MIT License (MIT).
- *
- * Copyright (c) SpongePowered <https://www.spongepowered.org>
- * Copyright (c) contributors
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-package io.akarin.server.mixin.lighting;
-
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.ThreadFactory;
-
-import javax.annotation.Nullable;
-
-import org.spongepowered.asm.mixin.Mixin;
-import com.google.common.util.concurrent.ThreadFactoryBuilder;
-
-import io.akarin.api.internal.Akari;
-import io.akarin.api.internal.mixin.IMixinChunk;
-import io.akarin.api.internal.mixin.IMixinWorldServer;
-import net.minecraft.server.BlockPosition;
-import net.minecraft.server.Chunk;
-import net.minecraft.server.EnumDirection;
-import net.minecraft.server.EnumSkyBlock;
-import net.minecraft.server.IBlockData;
-import net.minecraft.server.MCUtil;
-import net.minecraft.server.MathHelper;
-import net.minecraft.server.WorldServer;
-import net.minecraft.server.BlockPosition.PooledBlockPosition;
-
-@Mixin(value = WorldServer.class, remap = false)
-public abstract class MixinWorldServer extends MixinWorld implements IMixinWorldServer {
-    
-    private static final int NUM_XZ_BITS = 4;
-    private static final int NUM_SHORT_Y_BITS = 8;
-    private static final short XZ_MASK = 0xF;
-    private static final short Y_SHORT_MASK = 0xFF;
-    
-    private final static ThreadFactory SERVICE_FACTORY = new ThreadFactoryBuilder().setNameFormat("Akarin Async Lighting Thread - %1$d").build();
-    private final ExecutorService lightExecutorService = getExecutorService();
-    
-    private ExecutorService getExecutorService() {
-        return Executors.newFixedThreadPool(1, SERVICE_FACTORY);
-    }
-    
-    @Override
-    public boolean checkLightFor(EnumSkyBlock lightType, BlockPosition pos) { // PAIL: checkLightFor
-        return updateLightAsync(lightType, pos, null);
-    }
-    
-    public boolean checkLightAsync(EnumSkyBlock lightType, BlockPosition pos, Chunk currentChunk, List<Chunk> neighbors) {
-        // Sponge - This check is not needed as neighbors are checked in updateLightAsync
-        if (false && !this.areChunksLoaded(pos, 17, false)) {
-            return false;
-        } else {
-            final IMixinChunk spongeChunk = (IMixinChunk) currentChunk;
-            int i = 0;
-            int j = 0;
-            int current = this.getLightForAsync(lightType, pos, currentChunk, neighbors); // Sponge - use thread safe method
-            int rawLight = this.getRawBlockLightAsync(lightType, pos, currentChunk, neighbors); // Sponge - use thread safe method
-            int x = pos.getX();
-            int y = pos.getY();
-            int z = pos.getZ();
-            
-            if (rawLight > current) {
-                this.J[j++] = 133152; // PAIL: lightUpdateBlockList
-            } else if (rawLight < current) {
-                this.J[j++] = 133152 | current << 18; // PAIL: lightUpdateBlockList
-                
-                while (i < j) {
-                    int l1 = this.J[i++]; // PAIL: lightUpdateBlockList
-                    int i2 = (l1 & 63) - 32 + x;
-                    int j2 = (l1 >> 6 & 63) - 32 + y;
-                    int k2 = (l1 >> 12 & 63) - 32 + z;
-                    int l2 = l1 >> 18 & 15;
-                    BlockPosition blockpos = new BlockPosition(i2, j2, k2);
-                    int lightLevel = this.getLightForAsync(lightType, blockpos, currentChunk, neighbors); // Sponge - use thread safe method
-                    
-                    if (lightLevel == l2) {
-                        this.setLightForAsync(lightType, blockpos, 0, currentChunk, neighbors); // Sponge - use thread safe method
-                        
-                        if (l2 > 0) {
-                            int j3 = MathHelper.a(i2 - x); // abs
-                            int k3 = MathHelper.a(j2 - y);
-                            int l3 = MathHelper.a(k2 - z);
-                            
-                            if (j3 + k3 + l3 < 17) {
-                                PooledBlockPosition mutableBlockpos = PooledBlockPosition.aquire();
-                                
-                                for (EnumDirection enumfacing : EnumDirection.values()) {
-                                    int i4 = i2 + enumfacing.getAdjacentX();
-                                    int j4 = j2 + enumfacing.getAdjacentX();
-                                    int k4 = k2 + enumfacing.getAdjacentX();
-                                    mutableBlockpos.setValues(i4, j4, k4);
-                                    // Sponge start - get chunk safely
-                                    final Chunk pooledChunk = this.getLightChunk(mutableBlockpos, currentChunk, neighbors);
-                                    if (pooledChunk == null) {
-                                        continue;
-                                    }
-                                    int opacity = Math.max(1, pooledChunk.getBlockData(mutableBlockpos).c()); // PAIL: getLightOpacity
-                                    lightLevel = this.getLightForAsync(lightType, mutableBlockpos, currentChunk, neighbors);
-                                    // Sponge end
-                                    
-                                    if (lightLevel == l2 - opacity && j < this.J.length) { // PAIL: lightUpdateBlockList
-                                        this.J[j++] = i4 - x + 32 | j4 - y + 32 << 6 | k4 - z + 32 << 12 | l2 - opacity << 18; // PAIL: lightUpdateBlockList
-                                    }
-                                }
-                                
-                                mutableBlockpos.free();
-                            }
-                        }
-                    }
-                }
-                
-                i = 0;
-            }
-            
-            while (i < j) {
-                int i5 = this.J[i++]; // PAIL: lightUpdateBlockList
-                int j5 = (i5 & 63) - 32 + x;
-                int k5 = (i5 >> 6 & 63) - 32 + y;
-                int l5 = (i5 >> 12 & 63) - 32 + z;
-                BlockPosition blockpos1 = new BlockPosition(j5, k5, l5);
-                int i6 = this.getLightForAsync(lightType, blockpos1, currentChunk, neighbors); // Sponge - use thread safe method
-                int j6 = this.getRawBlockLightAsync(lightType, blockpos1, currentChunk, neighbors); // Sponge - use thread safe method
-                
-                if (j6 != i6) {
-                    this.setLightForAsync(lightType, blockpos1, j6, currentChunk, neighbors); // Sponge - use thread safe method
-                    
-                    if (j6 > i6) {
-                        int k6 = Math.abs(j5 - x);
-                        int l6 = Math.abs(k5 - y);
-                        int i7 = Math.abs(l5 - z);
-                        boolean flag = j < this.J.length - 6; // PAIL: lightUpdateBlockList
-                        
-                        if (k6 + l6 + i7 < 17 && flag) {
-                            // Sponge start - use thread safe method getLightForAsync
-                            if (this.getLightForAsync(lightType, blockpos1.west(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 - 1 - x + 32 + (k5 - y + 32 << 6) + (l5 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-
-                            if (this.getLightForAsync(lightType, blockpos1.east(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 + 1 - x + 32 + (k5 - y + 32 << 6) + (l5 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-
-                            if (this.getLightForAsync(lightType, blockpos1.down(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 - x + 32 + (k5 - 1 - y + 32 << 6) + (l5 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-
-                            if (this.getLightForAsync(lightType, blockpos1.up(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 - x + 32 + (k5 + 1 - y + 32 << 6) + (l5 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-
-                            if (this.getLightForAsync(lightType, blockpos1.north(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 - x + 32 + (k5 - y + 32 << 6) + (l5 - 1 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-
-                            if (this.getLightForAsync(lightType, blockpos1.south(), currentChunk, neighbors) < j6) {
-                                this.J[j++] = j5 - x + 32 + (k5 - y + 32 << 6) + (l5 + 1 - z + 32 << 12); // PAIL: lightUpdateBlockList
-                            }
-                            // Sponge end
-                        }
-                    }
-                }
-            }
-            
-            // Sponge start - Asynchronous light updates
-            spongeChunk.getQueuedLightingUpdates(lightType).remove((Short) this.blockPosToShort(pos));
-            spongeChunk.getPendingLightUpdates().decrementAndGet();
-            for (Chunk neighborChunk : neighbors) {
-                final IMixinChunk neighbor = (IMixinChunk) neighborChunk;
-                neighbor.getPendingLightUpdates().decrementAndGet();
-            }
-            // Sponge end
-            return true;
-        }
-    }
-    
-    @Override
-    public boolean updateLightAsync(EnumSkyBlock lightType, BlockPosition pos, @Nullable Chunk currentChunk) {
-        if (this.getMinecraftServer().isStopped() || this.lightExecutorService.isShutdown()) {
-            return false;
-        }
-        
-        if (currentChunk == null) {
-            currentChunk = MCUtil.getLoadedChunkWithoutMarkingActive(chunkProvider, pos.getX() >> 4, pos.getZ() >> 4);
-        }
-        
-        final IMixinChunk spongeChunk = (IMixinChunk) currentChunk;
-        if (currentChunk == null || currentChunk.isUnloading() || !spongeChunk.areNeighborsLoaded()) {
-            return false;
-        }
-        
-        final short shortPos = this.blockPosToShort(pos);
-        if (spongeChunk.getQueuedLightingUpdates(lightType).contains(shortPos)) {
-            return false;
-        }
-        
-        final Chunk chunk = currentChunk;
-        spongeChunk.getQueuedLightingUpdates(lightType).add(shortPos);
-        spongeChunk.getPendingLightUpdates().incrementAndGet();
-        spongeChunk.setLightUpdateTime(chunk.getWorld().getTime());
-        
-        List<Chunk> neighbors = spongeChunk.getNeighbors();
-        // add diagonal chunks
-        Chunk southEastChunk = ((IMixinChunk) spongeChunk.getNeighborChunk(0)).getNeighborChunk(2);
-        Chunk southWestChunk = ((IMixinChunk) spongeChunk.getNeighborChunk(0)).getNeighborChunk(3);
-        Chunk northEastChunk = ((IMixinChunk) spongeChunk.getNeighborChunk(1)).getNeighborChunk(2);
-        Chunk northWestChunk = ((IMixinChunk) spongeChunk.getNeighborChunk(1)).getNeighborChunk(3);
-        if (southEastChunk != null) {
-            neighbors.add(southEastChunk);
-        }
-        if (southWestChunk != null) {
-            neighbors.add(southWestChunk);
-        }
-        if (northEastChunk != null) {
-            neighbors.add(northEastChunk);
-        }
-        if (northWestChunk != null) {
-            neighbors.add(northWestChunk);
-        }
-        
-        for (Chunk neighborChunk : neighbors) {
-            final IMixinChunk neighbor = (IMixinChunk) neighborChunk;
-            neighbor.getPendingLightUpdates().incrementAndGet();
-            neighbor.setLightUpdateTime(chunk.getWorld().getTime());
-        }
-        
-        if (Akari.isPrimaryThread()) { // Akarin
-            this.lightExecutorService.execute(() -> {
-                this.checkLightAsync(lightType, pos, chunk, neighbors);
-            });
-        } else {
-            this.checkLightAsync(lightType, pos, chunk, neighbors);
-        }
-        
-        return true;
-    }
-    
-    @Override
-    public ExecutorService getLightingExecutor() {
-        return this.lightExecutorService;
-    }
-    
-    // Thread safe methods to retrieve a chunk during async light updates
-    // Each method avoids calling getLoadedChunk and instead accesses the passed neighbor chunk list to avoid concurrency issues
-    public Chunk getLightChunk(BlockPosition pos, Chunk currentChunk, List<Chunk> neighbors) {
-        if (currentChunk.a(pos.getX() >> 4, pos.getZ() >> 4)) { // PAIL: isAtLocation
-            if (currentChunk.isUnloading()) {
-                return null;
-            }
-            return currentChunk;
-        }
-        for (Chunk neighbor : neighbors) {
-            if (neighbor.a(pos.getX() >> 4, pos.getZ() >> 4)) { // PAIL: isAtLocation
-                if (neighbor.isUnloading()) {
-                    return null;
-                }
-                return neighbor;
-            }
-        }
-        
-        return null;
-    }
-    
-    private int getLightForAsync(EnumSkyBlock lightType, BlockPosition pos, Chunk currentChunk, List<Chunk> neighbors) {
-        if (pos.getY() < 0) {
-            pos = new BlockPosition(pos.getX(), 0, pos.getZ());
-        }
-        if (!pos.isValidLocation()) {
-            return lightType.c; // PAIL: defaultLightValue
-        }
-        
-        final Chunk chunk = this.getLightChunk(pos, currentChunk, neighbors);
-        if (chunk == null || chunk.isUnloading()) {
-            return lightType.c; // PAIL: defaultLightValue
-        }
-        
-        return chunk.getBrightness(lightType, pos);
-    }
-    
-    private int getRawBlockLightAsync(EnumSkyBlock lightType, BlockPosition pos, Chunk currentChunk, List<Chunk> neighbors) {
-        final Chunk chunk = getLightChunk(pos, currentChunk, neighbors);
-        if (chunk == null || chunk.isUnloading()) {
-            return lightType.c; // PAIL: defaultLightValue
-        }
-        if (lightType == EnumSkyBlock.SKY && chunk.c(pos)) { // PAIL: canSeeSky
-            return 15;
-        } else {
-            IBlockData blockData = chunk.getBlockData(pos);
-            int blockLight = blockData.d(); // getLightValue
-            int rawLight = lightType == EnumSkyBlock.SKY ? 0 : blockLight;
-            int opacity = blockData.c(); // PAIL: getLightOpacity
-            
-            if (opacity >= 15 && blockLight > 0) {
-                opacity = 1;
-            }
-            
-            if (opacity < 1) {
-                opacity = 1;
-            }
-            
-            if (opacity >= 15) {
-                return 0;
-            } else if (rawLight >= 14) {
-                return rawLight;
-            } else {
-                for (EnumDirection facing : EnumDirection.values()) {
-                    BlockPosition blockpos = pos.shift(facing);
-                    int current = this.getLightForAsync(lightType, blockpos, currentChunk, neighbors) - opacity;
-                    
-                    if (current > rawLight) {
-                        rawLight = current;
-                    }
-                    
-                    if (rawLight >= 14) {
-                        return rawLight;
-                    }
-                }
-                
-                return rawLight;
-            }
-        }
-    }
-
-    public void setLightForAsync(EnumSkyBlock type, BlockPosition pos, int lightValue, Chunk currentChunk, List<Chunk> neighbors) {
-        if (pos.isValidLocation()) {
-            final Chunk chunk = this.getLightChunk(pos, currentChunk, neighbors);
-            if (chunk != null && !chunk.isUnloading()) {
-                chunk.a(type, pos, lightValue); // PAIL: setLightFor
-                // this.notifyLightSet(pos); // client side
-            }
-        }
-    }
-    
-    private short blockPosToShort(BlockPosition pos) {
-        short serialized = (short) setNibble(0, pos.getX() & XZ_MASK, 0, NUM_XZ_BITS);
-        serialized = (short) setNibble(serialized, pos.getY() & Y_SHORT_MASK, 1, NUM_SHORT_Y_BITS);
-        serialized = (short) setNibble(serialized, pos.getZ() & XZ_MASK, 3, NUM_XZ_BITS);
-        return serialized;
-    }
-
-    /**
-     * Modifies bits in an integer.
-     *
-     * @param num Integer to modify
-     * @param data Bits of data to add
-     * @param which Index of nibble to start at
-     * @param bitsToReplace The number of bits to replace starting from nibble index
-     * @return The modified integer
-     */
-    private int setNibble(int num, int data, int which, int bitsToReplace) {
-        return (num & ~(bitsToReplace << (which * 4)) | (data << (which * 4)));
-    }
-}

sources/src/main/java/io/akarin/server/mixin/nsc/NonblockingServerConnection.java

@@ -77,7 +77,7 @@ public abstract class NonblockingServerConnection {
         Class<? extends ServerChannel> channelClass;
         EventLoopGroup loopGroup;
         
-        if (Epoll.isAvailable() && this.server.af()) { // PAIL: MinecraftServer::useNativeTransport
+        if (Epoll.isAvailable() && this.server.af()) { // OBFHELPER: MinecraftServer::useNativeTransport
             channelClass = EpollServerSocketChannel.class;
             loopGroup = ServerConnection.b.c();
             logger.info("Using epoll channel type");
@@ -122,7 +122,7 @@ public abstract class NonblockingServerConnection {
         }
     }
     
-    @Shadow public volatile boolean d; // PAIL: neverTerminate
+    @Shadow public volatile boolean d; // OBFHELPER: neverTerminate
     /**
      * Shuts down all open endpoints
      */
@@ -139,7 +139,7 @@ public abstract class NonblockingServerConnection {
     
     public void processPackets(NetworkManager manager) {
         try {
-            manager.a(); // PAIL: NetworkManager::processReceivedPackets
+            manager.a(); // OBFHELPER: NetworkManager::processReceivedPackets
         } catch (Exception ex) {
             logger.warn("Failed to handle packet for {}", manager.getSocketAddress(), ex);
             final ChatComponentText message = new ChatComponentText("Internal server error");
@@ -168,7 +168,7 @@ public abstract class NonblockingServerConnection {
             Iterator<NetworkManager> it = networkManagers.iterator();
             while (it.hasNext()) {
                 NetworkManager manager = it.next();
-                if (manager.h()) continue; // PAIL: NetworkManager::hasNoChannel
+                if (manager.h()) continue; // OBFHELPER: NetworkManager::hasNoChannel
                 
                 if (manager.isConnected()) {
                     processPackets(manager);

sources/src/main/java/io/akarin/server/mixin/nsc/OptimisticNetworkManager.java

@@ -1,14 +1,14 @@
 package io.akarin.server.mixin.nsc;
 
 import java.util.Queue;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
-
 import org.spongepowered.asm.mixin.Final;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Overwrite;
 import org.spongepowered.asm.mixin.Shadow;
 
-import io.akarin.api.internal.collections.CheckedConcurrentLinkedQueue;
+import com.googlecode.concurentlocks.ReentrantReadWriteUpdateLock;
+
+import io.akarin.api.internal.utils.CheckedConcurrentLinkedQueue;
 import io.netty.channel.Channel;
 import io.netty.util.concurrent.Future;
 import io.netty.util.concurrent.GenericFutureListener;
@@ -21,21 +21,22 @@ import net.minecraft.server.PacketPlayOutMapChunk;
 public abstract class OptimisticNetworkManager {
     @Shadow public Channel channel;
     @Shadow(aliases = "i") @Final private Queue<NetworkManager.QueuedPacket> packets;
-    @Shadow(aliases = "j") @Final private ReentrantReadWriteLock queueLock;
+    @Shadow(aliases = "j") @Final private ReentrantReadWriteUpdateLock queueLock;
     
     @Shadow public abstract Queue<NetworkManager.QueuedPacket> getPacketQueue();
     @Shadow public abstract void dispatchPacket(Packet<?> packet, GenericFutureListener<? extends Future<? super Void>>[] genericFutureListeners);
     
-    private static final QueuedPacket SIGNAL_PACKET = new QueuedPacket(null, null);
+    @SuppressWarnings("unchecked")
+    private static final QueuedPacket SIGNAL_PACKET = new QueuedPacket(null);
     
-    @Overwrite // PAIL: trySendQueue
+    @Overwrite // OBFHELPER: trySendQueue
     private boolean m() {
         if (this.channel != null && this.channel.isOpen()) {
             if (this.packets.isEmpty()) { // return if the packet queue is empty so that the write lock by Anti-Xray doesn't affect the vanilla performance at all
                 return true;
             }
 
-            this.queueLock.readLock().lock();
+            this.queueLock.updateLock().lock();
             try {
                 while (!this.packets.isEmpty()) {
                     NetworkManager.QueuedPacket packet = ((CheckedConcurrentLinkedQueue<QueuedPacket>) getPacketQueue()).poll(item -> {
@@ -51,7 +52,7 @@ public abstract class OptimisticNetworkManager {
                     }
                 }
             } finally {
-                this.queueLock.readLock().unlock();
+                this.queueLock.updateLock().unlock();
             }
             
         }

sources/src/main/java/io/akarin/server/mixin/optimization/MixinEntity.java

@@ -0,0 +1,34 @@
+package io.akarin.server.mixin.optimization;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Overwrite;
+import org.spongepowered.asm.mixin.Shadow;
+
+import net.minecraft.server.AxisAlignedBB;
+import net.minecraft.server.Entity;
+import net.minecraft.server.Material;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.World;
+
+@Mixin(value = Entity.class, remap = false)
+public abstract class MixinEntity {
+    @Shadow public World world;
+    @Shadow public abstract AxisAlignedBB getBoundingBox();
+    
+    private boolean isInLava;
+    private int lastLavaCheck = Integer.MIN_VALUE;
+    
+    @Overwrite // OBFHELPER: isInLava
+    public boolean au() {
+        /*
+         * This originally comes from Migot (https://github.com/Poweruser/Migot/commit/cafbf1707107d2a3aa6232879f305975bb1f0285)
+         * Thanks @Poweruser
+         */
+        int currentTick = MinecraftServer.currentTick;
+        if (this.lastLavaCheck != currentTick) {
+            this.lastLavaCheck = currentTick;
+            this.isInLava = this.world.a(this.getBoundingBox().grow(-0.10000000149011612D, -0.4000000059604645D, -0.10000000149011612D), Material.LAVA);
+        }
+        return this.isInLava;
+    }
+}

sources/src/main/java/io/akarin/server/mixin/optimization/PandaRedstoneWire.java

@@ -18,7 +18,6 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
 
-import io.akarin.api.internal.Akari;
 import net.minecraft.server.BaseBlockPosition;
 import net.minecraft.server.Block;
 import net.minecraft.server.BlockDiodeAbstract;
@@ -148,10 +147,11 @@ public abstract class PandaRedstoneWire extends Block {
         
         while (!turnOff.isEmpty()) {
             BlockPosition pos = turnOff.remove(0);
+            if (pos == null) continue; // Akarin
             IBlockData state = worldIn.getType(pos);
             int oldPower = state.get(BlockRedstoneWire.POWER).intValue();
             this.canProvidePower = false;
-            int blockPower = worldIn.z(pos); // PAIL: isBlockIndirectlyGettingPowered
+            int blockPower = worldIn.z(pos); // OBFHELPER: isBlockIndirectlyGettingPowered
             this.canProvidePower = true;
             int wirePower = this.getSurroundingWirePower(worldIn, pos);
             
@@ -186,10 +186,11 @@ public abstract class PandaRedstoneWire extends Block {
         // Now all needed wires are turned off. Time to turn them on again if there is a power source.
         while (!this.turnOn.isEmpty()) {
             BlockPosition pos = this.turnOn.remove(0);
+            if (pos == null) continue; // Akarin
             IBlockData state = worldIn.getType(pos);
             int oldPower = state.get(BlockRedstoneWire.POWER).intValue();
             this.canProvidePower = false;
-            int blockPower = worldIn.z(pos); // PAIL: isBlockIndirectlyGettingPowered
+            int blockPower = worldIn.z(pos); // OBFHELPER: isBlockIndirectlyGettingPowered
             this.canProvidePower = true;
             int wirePower = this.getSurroundingWirePower(worldIn, pos);
             // Lower the strength as it moved a block
@@ -265,11 +266,11 @@ public abstract class PandaRedstoneWire extends Block {
         }
         for (EnumDirection facingVertical : facingsVertical) {
             BlockPosition offsetPos = pos.shift(facingVertical);
-            boolean solidBlock = worldIn.getType(offsetPos).k(); // PAIL: isBlockNormalCube
+            boolean solidBlock = worldIn.getType(offsetPos).k(); // OBFHELPER: isBlockNormalCube
             for (EnumDirection facingHorizontal : facingsHorizontal) {
                 // wire can travel upwards if the block on top doesn't cut the wire (is non-solid)
                 // it can travel down if the block below is solid and the block "diagonal" doesn't cut off the wire (is non-solid) 
-                if ((facingVertical == EnumDirection.UP && !solidBlock) || (facingVertical == EnumDirection.DOWN && solidBlock && !worldIn.getType(offsetPos.shift(facingHorizontal)).k())) { // PAIL: isBlockNormalCube
+                if ((facingVertical == EnumDirection.UP && !solidBlock) || (facingVertical == EnumDirection.DOWN && solidBlock && !worldIn.getType(offsetPos.shift(facingHorizontal)).k())) { // OBFHELPER: isBlockNormalCube
                     this.addWireToList(worldIn, offsetPos.shift(facingHorizontal), ownPower);
                 }
             }
@@ -293,10 +294,10 @@ public abstract class PandaRedstoneWire extends Block {
             wirePower = this.getPower(worldIn, offsetPos, wirePower);
             
             // Block below the wire need to be solid (Upwards diode of slabs/stairs/glowstone) and no block should cut the wire
-            if(worldIn.getType(offsetPos).l() && !worldIn.getType(pos.up()).l()) { // PAIL: isNormalCube
+            if(worldIn.getType(offsetPos).l() && !worldIn.getType(pos.up()).l()) { // OBFHELPER: isNormalCube
                 wirePower = this.getPower(worldIn, offsetPos.up(), wirePower);
                 // Only get from power below if no block is cutting the wire
-            } else if (!worldIn.getType(offsetPos).l()) { // PAIL: isNormalCube
+            } else if (!worldIn.getType(offsetPos).l()) { // OBFHELPER: isNormalCube
                 wirePower = this.getPower(worldIn, offsetPos.down(), wirePower);
             }
         }
@@ -328,7 +329,7 @@ public abstract class PandaRedstoneWire extends Block {
         // Later add blocks around the surrounding blocks that get powered
         for (EnumDirection facing : facings) {
             BlockPosition offsetPos = pos.shift(facing);
-            if (!connectedSides.contains(facing.opposite()) && facing != EnumDirection.DOWN || !worldIn.getType(offsetPos).l()) continue; // PAIL: isNormalCube
+            if (!connectedSides.contains(facing.opposite()) && facing != EnumDirection.DOWN || !worldIn.getType(offsetPos).l()) continue; // OBFHELPER: isNormalCube
             for (EnumDirection facing1 : facings) {
                 if (this.canBlockBePoweredFromSide(worldIn.getType(offsetPos.shift(facing1)), facing1, false))
                     set.add(offsetPos.shift(facing1));
@@ -413,7 +414,7 @@ public abstract class PandaRedstoneWire extends Block {
      */
     private void addAllSurroundingBlocks(BlockPosition pos, Set<BlockPosition> set) {
         for (BaseBlockPosition vect : surroundingBlocksOffset) {
-            set.add(pos.a(vect)); // PAIL: add
+            set.add(pos.a(vect)); // OBFHELPER: add
         }
     }
 
@@ -446,7 +447,7 @@ public abstract class PandaRedstoneWire extends Block {
     public void onPlace(World world, BlockPosition pos, IBlockData state) {
         this.updateSurroundingRedstone(world, pos);
         for (BaseBlockPosition vec : surroundingBlocksOffset) {
-            world.applyPhysics(pos.a(vec), this, false); // PAIL: add
+            world.applyPhysics(pos.a(vec), this, false); // OBFHELPER: add
         }
     }
     
@@ -463,7 +464,7 @@ public abstract class PandaRedstoneWire extends Block {
         super.remove(world, pos, state);
         this.updateSurroundingRedstone(world, pos);
         for (BaseBlockPosition vec : surroundingBlocksOffset) {
-            world.applyPhysics(pos.a(vec), this, false); // PAIL: add
+            world.applyPhysics(pos.a(vec), this, false); // OBFHELPER: add
         }
     }
 
@@ -478,7 +479,7 @@ public abstract class PandaRedstoneWire extends Block {
      */
     @Override
     @Overwrite
-    public int b(IBlockData blockState, IBlockAccess blockAccess, BlockPosition pos, EnumDirection side) { // PAIL: getWeakPower
+    public int b(IBlockData blockState, IBlockAccess blockAccess, BlockPosition pos, EnumDirection side) { // OBFHELPER: getWeakPower
         if (!this.canProvidePower) {
             return 0;
         } else {
@@ -495,14 +496,14 @@ public abstract class PandaRedstoneWire extends Block {
         
         if (block == Blocks.REDSTONE_WIRE) {
             return true;
-        } else if (Blocks.UNPOWERED_REPEATER.D(blockState)) { // PAIL: isSameDiode
+        } else if (Blocks.UNPOWERED_REPEATER.D(blockState)) { // OBFHELPER: isSameDiode
             EnumDirection enumdirection1 = blockState.get(BlockRepeater.FACING);
             
             return enumdirection1 == side || enumdirection1.opposite() == side;
         } else if (Blocks.dk == blockState.getBlock()) {
-            return side == blockState.get(BlockObserver.FACING); // PAIL: OBSERVER
+            return side == blockState.get(BlockObserver.FACING); // OBFHELPER: OBSERVER
         } else {
-            return blockState.m() && side != null; // PAIL: canProvidePower
+            return blockState.m() && side != null; // OBFHELPER: canProvidePower
         }
     }
     

sources/src/main/java/io/akarin/server/mixin/optimization/WeakEnchantmentManager.java

@@ -50,23 +50,23 @@ public abstract class WeakEnchantmentManager {
     
     @Overwrite
     public static int a(Iterable<ItemStack> iterable, DamageSource damageSource) {
-        protection.a = 0; // PAIL: damageModifier
+        protection.a = 0; // OBFHELPER: damageModifier
         protection.b = damageSource;
-        a(protection, iterable); // PAIL: applyEnchantmentModifierArray
+        a(protection, iterable); // OBFHELPER: applyEnchantmentModifierArray
         protection.b = null; // Akarin - Remove reference to Damagesource
         return protection.a;
     }
     
     @Overwrite
-    public static void a(EntityLiving user, Entity attacker) { // PAIL: applyThornEnchantments
+    public static void a(EntityLiving user, Entity attacker) { // OBFHELPER: applyThornEnchantments
         thorns.b = attacker;
         thorns.a = user;
         if (user != null) {
-            a(thorns, user.aQ()); // PAIL: applyEnchantmentModifierArray - getEquipmentAndArmor
+            a(thorns, user.aQ()); // OBFHELPER: applyEnchantmentModifierArray - getEquipmentAndArmor
         }
         
         if (attacker instanceof EntityHuman) {
-            a(thorns, user.getItemInMainHand()); // PAIL: applyEnchantmentModifier
+            a(thorns, user.getItemInMainHand()); // OBFHELPER: applyEnchantmentModifier
         }
         
         // Akarin Start - remove references to entity objects to avoid memory leaks
@@ -76,15 +76,15 @@ public abstract class WeakEnchantmentManager {
     }
 
     @Overwrite
-    public static void b(EntityLiving user, Entity target) { // PAIL: applyArthropodEnchantments
+    public static void b(EntityLiving user, Entity target) { // OBFHELPER: applyArthropodEnchantments
         arthropods.a = user;
         arthropods.b = target;
         if (user != null) {
-            a(arthropods, user.aQ()); // PAIL: applyEnchantmentModifierArray - getEquipmentAndArmor
+            a(arthropods, user.aQ()); // OBFHELPER: applyEnchantmentModifierArray - getEquipmentAndArmor
         }
         
         if (user instanceof EntityHuman) {
-            a(arthropods, user.getItemInMainHand()); // PAIL: applyEnchantmentModifier
+            a(arthropods, user.getItemInMainHand()); // OBFHELPER: applyEnchantmentModifier
         }
         
         // Akarin Start - remove references to entity objects to avoid memory leaks

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntity.java

@@ -33,7 +33,7 @@ import io.akarin.api.internal.mixin.IMixinRealTimeTicking;
 import net.minecraft.server.Entity;
 import net.minecraft.server.World;
 
-@Mixin(value = Entity.class, remap = false)
+@Mixin(value = Entity.class, remap = false, priority = 1001)
 public abstract class MixinEntity {
     private static final String ENTITY_RIDABLE_COOLDOWN_FIELD = "Lnet/minecraft/entity/Entity;j:I"; // PUTFIELD: rideCooldown
     private static final String ENTITY_PORTAL_COUNTER_FIELD = "Lnet/minecraft/entity/Entity;al:I"; // PUTFIELD: portalCounter
@@ -41,16 +41,16 @@ public abstract class MixinEntity {
     @Shadow protected int al;
     @Shadow public World world;
     
-    // PAIL: onEntityUpdate
+    // OBFHELPER: onEntityUpdate
     @Redirect(method = "Y()V", at = @At(value = "FIELD", target = ENTITY_RIDABLE_COOLDOWN_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupEntityCooldown(Entity self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.world).getRealTimeTicks();
-        this.j = Math.max(0, this.j - ticks); // PAIL: rideCooldown
+        this.j = Math.max(0, this.j - ticks); // OBFHELPER: rideCooldown
     }
     
     @Redirect(method = "Y()V", at = @At(value = "FIELD", target = ENTITY_PORTAL_COUNTER_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupPortalCounter(Entity self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.world).getRealTimeTicks();
-        this.al += ticks; // PAIL: portalCounter
+        this.al += ticks; // OBFHELPER: portalCounter
     }
 }

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityAgeable.java

@@ -34,7 +34,7 @@ import net.minecraft.server.EntityAgeable;
 public abstract class MixinEntityAgeable {
     private static final String ENTITY_AGEABLE_SET_GROWING_AGE_METHOD = "Lnet/minecraft/entity/EntityAgeable;setAgeRaw(I)V";
     
-    // PAIL: onLivingUpdate
+    // OBFHELPER: onLivingUpdate
     @Redirect(method = "n()V", at = @At(value = "INVOKE", target = ENTITY_AGEABLE_SET_GROWING_AGE_METHOD, ordinal = 0))
     public void fixupGrowingUp(EntityAgeable self, int age) {
         // Subtract the one the original update method added

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityExperienceOrb.java

@@ -37,19 +37,19 @@ import net.minecraft.server.EntityExperienceOrb;
 public abstract class MixinEntityExperienceOrb {
     private static final String ENTITY_XP_DELAY_PICKUP_FIELD = "Lnet/minecraft/entity/item/EntityExperienceOrb;c:I"; // PUTFIELD: delayBeforeCanPickup
     private static final String ENTITY_XP_AGE_FIELD = "Lnet/minecraft/entity/item/EntityExperienceOrb;b:I"; // PUTFIELD: xpOrbAge
-    @Shadow public int c; // PAIL: delayBeforeCanPickup
-    @Shadow public int b; // PAIL: xpOrbAge
+    @Shadow public int c; // OBFHELPER: delayBeforeCanPickup
+    @Shadow public int b; // OBFHELPER: xpOrbAge
     
-    // PAIL: onUpdate
+    // OBFHELPER: onUpdate
     @Redirect(method = "B_()V", at = @At(value = "FIELD", target = ENTITY_XP_DELAY_PICKUP_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupPickupDelay(EntityExperienceOrb self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();
-        this.c = Math.max(0, this.c - ticks); // PAIL: delayBeforeCanPickup
+        this.c = Math.max(0, this.c - ticks); // OBFHELPER: delayBeforeCanPickup
     }
     
     @Redirect(method = "B_()V", at = @At(value = "FIELD", target = ENTITY_XP_AGE_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupAge(EntityExperienceOrb self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();
-        this.b += ticks; // PAIL: xpOrbAge
+        this.b += ticks; // OBFHELPER: xpOrbAge
     }
 }

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityHuman.java

@@ -40,11 +40,11 @@ public abstract class MixinEntityHuman {
     @Shadow public int bD;
     @Shadow private int sleepTicks;
     
-    // PAIL: onUpdate
+    // OBFHELPER: onUpdate
     @Redirect(method = "B_()V", at = @At(value = "FIELD", target = ENTITY_PLAYER_XP_COOLDOWN_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupXpCooldown(EntityHuman self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();
-        this.bD = Math.max(0, this.bD - ticks); // PAIL: xpCooldown
+        this.bD = Math.max(0, this.bD - ticks); // OBFHELPER: xpCooldown
     }
 
     @Redirect(method = "B_()V", at = @At(value = "FIELD", target = ENTITY_PLAYER_SLEEP_TIMER_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityInsentient.java

@@ -42,7 +42,7 @@ public abstract class MixinEntityInsentient extends EntityLiving {
         super(world);
     }
     
-    @Redirect(method = "doTick", at = @At(value = "FIELD", target = ENTITY_LIVING_AGE_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
+    @Redirect(method = "doTick()V", at = @At(value = "FIELD", target = ENTITY_LIVING_AGE_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupEntityDespawnAge(EntityInsentient self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();
         this.ticksFarFromPlayer += ticks;

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityItem.java

@@ -40,7 +40,7 @@ public abstract class MixinEntityItem {
     @Shadow public int age;
     @Shadow private int pickupDelay;
     
-    // PAIL: onUpdate
+    // OBFHELPER: onUpdate
     @Redirect(method = "B_()V", at = @At(value = "FIELD", target = ENTITY_ITEM_DELAY_PICKUP_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupPickupDelay(EntityItem self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityPlayer.java

@@ -42,7 +42,7 @@ public abstract class MixinEntityPlayer extends Entity {
         super(worldIn);
     }
     
-    // PAIL: decrementTimeUntilPortal
+    // OBFHELPER: decrementTimeUntilPortal
     @Redirect(method = "I()V", at = @At(value = "FIELD", target = ENTITY_PLAYER_MP_PORTAL_COOLDOWN_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupPortalCooldown(EntityPlayer self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinEntityZombieVillager.java

@@ -38,7 +38,7 @@ public abstract class MixinEntityZombieVillager {
     
     @Shadow(aliases = "du") protected abstract int getConversionProgress();
     
-    // PAIL: onUpdate
+    // OBFHELPER: onUpdate
     @Redirect(method = "B_()V", at = @At(value = "INVOKE", target = ENTITY_ZOMBIE_GET_CONVERSION_BOOST_METHOD, ordinal = 0))
     public int fixupConversionTimeBoost(EntityZombieVillager self) {
         int ticks = (int) ((IMixinRealTimeTicking) self.getWorld()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinMinecraftServer.java

@@ -13,7 +13,7 @@ public abstract class MixinMinecraftServer implements IMixinRealTimeTicking {
     private static long lastTickNanos = System.nanoTime();
     private static long realTimeTicks = 1;
     
-    @Inject(method = "C()V", at = @At("HEAD")) // PAIL: fullTick
+    @Inject(method = "C()V", at = @At("HEAD")) // OBFHELPER: fullTick
     public void onTickUpdateRealTimeTicks(CallbackInfo ci) {
         long currentNanos = System.nanoTime();
         realTimeTicks = (currentNanos - lastTickNanos) / 50000000;

sources/src/main/java/io/akarin/server/mixin/realtime/MixinPlayerConnection.java

@@ -43,7 +43,7 @@ public abstract class MixinPlayerConnection {
     @Shadow(aliases = "j") private int itemDropThreshold;
     @Shadow @Final private MinecraftServer minecraftServer;
     
-    // PAIL: update
+    // OBFHELPER: update
     @Redirect(method = "e()V", at = @At(value = "FIELD", target = NET_HANDLER_PLAY_CHAT_SPAM_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupChatSpamCheck(PlayerConnection self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.minecraftServer).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinPlayerInteractManager.java

@@ -40,7 +40,7 @@ public abstract class MixinPlayerInteractManager {
     @Shadow public World world;
     @Shadow private int currentTick;
     
-    // PAIL: updateBlockRemoving
+    // OBFHELPER: updateBlockRemoving
     @Redirect(method = "a()V", at = @At(value = "FIELD", target = PLAYER_INTERACTION_BLOCK_DAMAGE_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupDiggingTime(PlayerInteractManager self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.world.getMinecraftServer()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinTileEntityBrewingStand.java

@@ -39,7 +39,7 @@ public abstract class MixinTileEntityBrewingStand extends TileEntity {
     private static final String BREWING_STAND_BREW_TIME_FIELD = "Lnet/minecraft/tileentity/TileEntityBrewingStand;brewTime:I";
     @Shadow private int brewTime;
     
-    // PAIL: update
+    // OBFHELPER: update
     @Redirect(method = "e()V", at = @At(value = "FIELD", target = BREWING_STAND_BREW_TIME_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupBrewTime(TileEntityBrewingStand self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.getWorld()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinTileEntityFurnace.java

@@ -43,7 +43,7 @@ public abstract class MixinTileEntityFurnace extends TileEntity {
     @Shadow private int cookTime;
     @Shadow private int cookTimeTotal;
     
-    // PAIL: update
+    // OBFHELPER: update
     @Redirect(method = "e()V", at = @At(value = "FIELD", target = FURNACE_BURN_TIME_FIELD, opcode = Opcodes.PUTFIELD, ordinal = 0))
     public void fixupBurnTime(TileEntityFurnace self, int modifier) {
         int ticks = (int) ((IMixinRealTimeTicking) this.getWorld()).getRealTimeTicks();

sources/src/main/java/io/akarin/server/mixin/realtime/MixinWorld.java

@@ -32,7 +32,7 @@ import io.akarin.api.internal.mixin.IMixinRealTimeTicking;
 import net.minecraft.server.MinecraftServer;
 import net.minecraft.server.World;
 
-@Mixin(value = World.class, remap = false, priority = 1002)
+@Mixin(value = World.class, remap = false, priority = 1001)
 public abstract class MixinWorld implements IMixinRealTimeTicking {
     @Shadow @Nullable public abstract MinecraftServer getMinecraftServer();
 

sources/src/main/java/net/minecraft/server/ChunkRegionLoader.java

@@ -0,0 +1,623 @@
+package net.minecraft.server;
+
+import com.google.common.collect.Maps;
+import java.io.File;
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import javax.annotation.Nullable;
+import java.util.concurrent.ConcurrentLinkedQueue; // Paper
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+// Spigot start
+import java.util.function.Supplier;
+import org.spigotmc.SupplierUtils;
+// Spigot end
+
+/**
+ * Akarin Changes Note
+ * 1) Removes unneed synchronization (performance)
+ */
+public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
+
+    private ConcurrentLinkedQueue<QueuedChunk> queue = new ConcurrentLinkedQueue<>(); // Paper - Chunk queue improvements
+    private final Object lock = new Object(); // Paper - Chunk queue improvements
+    private static final Logger a = LogManager.getLogger();
+    private final Map<ChunkCoordIntPair, Supplier<NBTTagCompound>> b = Maps.newConcurrentMap(); // Spigot
+    // CraftBukkit
+    // private final Set<ChunkCoordIntPair> c = Collections.newSetFromMap(Maps.newConcurrentMap());
+    private final File d;
+    private final DataConverterManager e;
+    // private boolean f;
+    // CraftBukkit
+    private static final double SAVE_QUEUE_TARGET_SIZE = 625; // Spigot
+
+    public ChunkRegionLoader(File file, DataConverterManager dataconvertermanager) {
+        this.d = file;
+        this.e = dataconvertermanager;
+    }
+
+    // Paper start
+    private long queuedSaves = 0;
+    private final java.util.concurrent.atomic.AtomicLong processedSaves = new java.util.concurrent.atomic.AtomicLong(0L);
+    public int getQueueSize() { return queue.size(); }
+    public long getQueuedSaves() { return queuedSaves; }
+    public long getProcessedSaves() { return processedSaves.longValue(); }
+    // Paper end
+
+    // CraftBukkit start - Add async variant, provide compatibility
+    @Nullable
+    public Chunk a(World world, int i, int j) throws IOException {
+        world.timings.syncChunkLoadDataTimer.startTiming(); // Spigot
+        Object[] data = loadChunk(world, i, j);
+        world.timings.syncChunkLoadDataTimer.stopTiming(); // Spigot
+        if (data != null) {
+            Chunk chunk = (Chunk) data[0];
+            NBTTagCompound nbttagcompound = (NBTTagCompound) data[1];
+            loadEntities(chunk, nbttagcompound.getCompound("Level"), world);
+            return chunk;
+        }
+
+        return null;
+    }
+
+    public Object[] loadChunk(World world, int i, int j) throws IOException {
+        // CraftBukkit end
+        ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i, j);
+        NBTTagCompound nbttagcompound = SupplierUtils.getIfExists(this.b.get(chunkcoordintpair)); // Spigot
+
+        if (nbttagcompound == null) {
+            // CraftBukkit start
+            nbttagcompound = RegionFileCache.d(this.d, i, j);
+
+            if (nbttagcompound == null) {
+                return null;
+            }
+
+            nbttagcompound = this.e.a((DataConverterType) DataConverterTypes.CHUNK, nbttagcompound);
+            // CraftBukkit end
+        }
+
+        return this.a(world, i, j, nbttagcompound);
+    }
+
+    public boolean chunkExists(int i, int j) {
+        ChunkCoordIntPair chunkcoordintpair = new ChunkCoordIntPair(i, j);
+        Supplier<NBTTagCompound> nbttagcompound = this.b.get(chunkcoordintpair); // Spigot
+
+        return nbttagcompound != null ? true : RegionFileCache.chunkExists(this.d, i, j);
+    }
+
+    @Nullable
+    protected Object[] a(World world, int i, int j, NBTTagCompound nbttagcompound) { // CraftBukkit - return Chunk -> Object[]
+        if (!nbttagcompound.hasKeyOfType("Level", 10)) {
+            ChunkRegionLoader.a.error("Chunk file at {},{} is missing level data, skipping", Integer.valueOf(i), Integer.valueOf(j));
+            return null;
+        } else {
+            NBTTagCompound nbttagcompound1 = nbttagcompound.getCompound("Level");
+
+            if (!nbttagcompound1.hasKeyOfType("Sections", 9)) {
+                ChunkRegionLoader.a.error("Chunk file at {},{} is missing block data, skipping", Integer.valueOf(i), Integer.valueOf(j));
+                return null;
+            } else {
+                Chunk chunk = this.a(world, nbttagcompound1);
+
+                if (!chunk.a(i, j)) {
+                    ChunkRegionLoader.a.error("Chunk file at {},{} is in the wrong location; relocating. (Expected {}, {}, got {}, {})", Integer.valueOf(i), Integer.valueOf(j), Integer.valueOf(i), Integer.valueOf(j), Integer.valueOf(chunk.locX), Integer.valueOf(chunk.locZ));
+                    nbttagcompound1.setInt("xPos", i);
+                    nbttagcompound1.setInt("zPos", j);
+
+                    // CraftBukkit start - Have to move tile entities since we don't load them at this stage
+                    NBTTagList tileEntities = nbttagcompound.getCompound("Level").getList("TileEntities", 10);
+                    if (tileEntities != null) {
+                        for (int te = 0; te < tileEntities.size(); te++) {
+                            NBTTagCompound tileEntity = (NBTTagCompound) tileEntities.get(te);
+                            int x = tileEntity.getInt("x") - chunk.locX * 16;
+                            int z = tileEntity.getInt("z") - chunk.locZ * 16;
+                            tileEntity.setInt("x", i * 16 + x);
+                            tileEntity.setInt("z", j * 16 + z);
+                        }
+                    }
+                    // CraftBukkit end
+                    chunk = this.a(world, nbttagcompound1);
+                }
+
+                // CraftBukkit start
+                Object[] data = new Object[2];
+                data[0] = chunk;
+                data[1] = nbttagcompound;
+                return data;
+                // CraftBukkit end
+            }
+        }
+    }
+
+    public void saveChunk(World world, Chunk chunk, boolean unloaded) throws IOException, ExceptionWorldConflict { // Spigot
+        world.checkSession();
+
+        try {
+            NBTTagCompound nbttagcompound = new NBTTagCompound();
+            NBTTagCompound nbttagcompound1 = new NBTTagCompound();
+
+            nbttagcompound.set("Level", nbttagcompound1);
+            nbttagcompound.setInt("DataVersion", 1343);
+
+            // Spigot start
+            final long worldTime = world.getTime();
+            final boolean worldHasSkyLight = world.worldProvider.m();
+            saveEntities(nbttagcompound1, chunk, world);
+            Supplier<NBTTagCompound> completion = new Supplier<NBTTagCompound>() {
+                public NBTTagCompound get() {
+                    saveBody(nbttagcompound1, chunk, worldTime, worldHasSkyLight);
+                    return nbttagcompound;
+                }
+            };
+
+            this.a(chunk.k(), SupplierUtils.createUnivaluedSupplier(completion, unloaded && this.b.size() < SAVE_QUEUE_TARGET_SIZE));
+            // Spigot end
+        } catch (Exception exception) {
+            ChunkRegionLoader.a.error("Failed to save chunk", exception);
+        }
+
+    }
+
+    protected void a(ChunkCoordIntPair chunkcoordintpair, Supplier<NBTTagCompound> nbttagcompound) { // Spigot
+        // CraftBukkit
+        // if (!this.c.contains(chunkcoordintpair))
+        synchronized (lock) {  // Paper - Chunk queue improvements
+            this.b.put(chunkcoordintpair, nbttagcompound);
+        }
+        queuedSaves++; // Paper
+        queue.add(new QueuedChunk(chunkcoordintpair, nbttagcompound)); // Paper - Chunk queue improvements
+
+        FileIOThread.a().a(this);
+    }
+
+    public boolean a() {
+        // CraftBukkit start
+        return this.processSaveQueueEntry(false);
+    }
+
+    private /*synchronized*/ boolean processSaveQueueEntry(boolean logCompletion) { // Akarin - remove synchronization
+        // CraftBukkit start
+        // Paper start - Chunk queue improvements
+        QueuedChunk chunk = queue.poll();
+        if (chunk == null) {
+        // Paper - end
+            if (logCompletion) {
+                // CraftBukkit end
+                ChunkRegionLoader.a.info("ThreadedAnvilChunkStorage ({}): All chunks are saved", this.d.getName());
+            }
+
+            return false;
+        } else {
+            ChunkCoordIntPair chunkcoordintpair = chunk.coords; // Paper - Chunk queue improvements
+            processedSaves.incrementAndGet(); // Paper
+
+            boolean flag;
+
+            try {
+                // this.c.add(chunkcoordintpair);
+                NBTTagCompound nbttagcompound = SupplierUtils.getIfExists(chunk.compoundSupplier); // Spigot // Paper
+                // CraftBukkit
+
+                if (nbttagcompound != null) {
+                    int attempts = 0; Exception laste = null; while (attempts++ < 5) { // Paper
+                    try {
+                        this.b(chunkcoordintpair, nbttagcompound);
+                        laste = null; break; // Paper
+                    } catch (Exception exception) {
+                        //ChunkRegionLoader.a.error("Failed to save chunk", exception); // Paper
+                        laste = exception; // Paper
+                    }
+                    try {Thread.sleep(10);} catch (InterruptedException e) {e.printStackTrace();} } // Paper
+                    if (laste != null) { com.destroystokyo.paper.exception.ServerInternalException.reportInternalException(laste); MinecraftServer.LOGGER.error("Failed to save chunk", laste); } // Paper
+                }
+                synchronized (lock) { if (this.b.get(chunkcoordintpair) == chunk.compoundSupplier) { this.b.remove(chunkcoordintpair); } }// Paper - This will not equal if a newer version is still pending
+
+                flag = true;
+            } finally {
+                //this.b.remove(chunkcoordintpair, value); // CraftBukkit // Spigot // Paper
+            }
+
+            return flag;
+        }
+    }
+
+    private void b(ChunkCoordIntPair chunkcoordintpair, NBTTagCompound nbttagcompound) throws IOException {
+        // CraftBukkit start
+        RegionFileCache.e(this.d, chunkcoordintpair.x, chunkcoordintpair.z, nbttagcompound);
+
+        /*
+        NBTCompressedStreamTools.a(nbttagcompound, (DataOutput) dataoutputstream);
+        dataoutputstream.close();
+        */
+        // CraftBukkit end
+    }
+
+    public void b(World world, Chunk chunk) throws IOException {}
+
+    public void b() {}
+
+    public void c() {
+        try {
+            // this.f = true; // CraftBukkit
+
+            while (true) {
+                if (this.processSaveQueueEntry(true)) { // CraftBukkit
+                    continue;
+                }
+                break; // CraftBukkit - Fix infinite loop when saving chunks
+            }
+        } finally {
+            // this.f = false; // CraftBukkit
+        }
+
+    }
+
+    public static void a(DataConverterManager dataconvertermanager) {
+        dataconvertermanager.a(DataConverterTypes.CHUNK, new DataInspector() {
+            public NBTTagCompound a(DataConverter dataconverter, NBTTagCompound nbttagcompound, int i) {
+                if (nbttagcompound.hasKeyOfType("Level", 10)) {
+                    NBTTagCompound nbttagcompound1 = nbttagcompound.getCompound("Level");
+                    NBTTagList nbttaglist;
+                    int j;
+
+                    if (nbttagcompound1.hasKeyOfType("Entities", 9)) {
+                        nbttaglist = nbttagcompound1.getList("Entities", 10);
+
+                        for (j = 0; j < nbttaglist.size(); ++j) {
+                            nbttaglist.a(j, dataconverter.a(DataConverterTypes.ENTITY, (NBTTagCompound) nbttaglist.i(j), i));
+                        }
+                    }
+
+                    if (nbttagcompound1.hasKeyOfType("TileEntities", 9)) {
+                        nbttaglist = nbttagcompound1.getList("TileEntities", 10);
+
+                        for (j = 0; j < nbttaglist.size(); ++j) {
+                            nbttaglist.a(j, dataconverter.a(DataConverterTypes.BLOCK_ENTITY, (NBTTagCompound) nbttaglist.i(j), i));
+                        }
+                    }
+                }
+
+                return nbttagcompound;
+            }
+        });
+    }
+
+    private static void saveBody(NBTTagCompound nbttagcompound, Chunk chunk, long worldTime, boolean worldHasSkyLight) { // Spigot
+        nbttagcompound.setInt("xPos", chunk.locX);
+        nbttagcompound.setInt("zPos", chunk.locZ);
+        nbttagcompound.setLong("LastUpdate", worldTime); // Spigot
+        nbttagcompound.setIntArray("HeightMap", chunk.r());
+        nbttagcompound.setBoolean("TerrainPopulated", chunk.isDone());
+        nbttagcompound.setBoolean("LightPopulated", chunk.v());
+        nbttagcompound.setLong("InhabitedTime", chunk.x());
+        ChunkSection[] achunksection = chunk.getSections();
+        NBTTagList nbttaglist = new NBTTagList();
+        boolean flag = worldHasSkyLight; // Spigot
+        ChunkSection[] achunksection1 = achunksection;
+        int i = achunksection.length;
+
+        NBTTagCompound nbttagcompound1;
+
+        for (int j = 0; j < i; ++j) {
+            ChunkSection chunksection = achunksection1[j];
+
+            if (chunksection != Chunk.a) {
+                nbttagcompound1 = new NBTTagCompound();
+                nbttagcompound1.setByte("Y", (byte) (chunksection.getYPosition() >> 4 & 255));
+                byte[] abyte = new byte[4096];
+                NibbleArray nibblearray = new NibbleArray();
+                NibbleArray nibblearray1 = chunksection.getBlocks().exportData(abyte, nibblearray);
+
+                nbttagcompound1.setByteArray("Blocks", abyte);
+                nbttagcompound1.setByteArray("Data", nibblearray.asBytes());
+                if (nibblearray1 != null) {
+                    nbttagcompound1.setByteArray("Add", nibblearray1.asBytes());
+                }
+
+                nbttagcompound1.setByteArray("BlockLight", chunksection.getEmittedLightArray().asBytes());
+                if (flag) {
+                    nbttagcompound1.setByteArray("SkyLight", chunksection.getSkyLightArray().asBytes());
+                } else {
+                    nbttagcompound1.setByteArray("SkyLight", new byte[chunksection.getEmittedLightArray().asBytes().length]);
+                }
+
+                nbttaglist.add(nbttagcompound1);
+            }
+        }
+
+        nbttagcompound.set("Sections", nbttaglist);
+        nbttagcompound.setByteArray("Biomes", chunk.getBiomeIndex());
+
+        // Spigot start - End this method here and split off entity saving to another method
+    }
+
+    private static void saveEntities(NBTTagCompound nbttagcompound, Chunk chunk, World world) {
+        int i;
+        NBTTagCompound nbttagcompound1;
+        // Spigot end
+
+        chunk.g(false);
+        NBTTagList nbttaglist1 = new NBTTagList();
+
+        Iterator iterator;
+
+        List<Entity> toUpdate = new java.util.ArrayList<>(); // Paper
+        for (i = 0; i < chunk.getEntitySlices().length; ++i) {
+            iterator = chunk.getEntitySlices()[i].iterator();
+
+            while (iterator.hasNext()) {
+                Entity entity = (Entity) iterator.next();
+                // Paper start
+                if ((int)Math.floor(entity.locX) >> 4 != chunk.locX || (int)Math.floor(entity.locZ) >> 4 != chunk.locZ) {
+                    LogManager.getLogger().warn(entity + " is not in this chunk, skipping save. This a bug fix to a vanilla bug. Do not report this to PaperMC please.");
+                    toUpdate.add(entity);
+                    continue;
+                }
+                if (entity.dead) {
+                    continue;
+                }
+                // Paper end
+
+                nbttagcompound1 = new NBTTagCompound();
+                if (entity.d(nbttagcompound1)) {
+                    chunk.g(true);
+                    nbttaglist1.add(nbttagcompound1);
+                }
+            }
+        }
+        // Paper start - move entities to the correct chunk
+        for (Entity entity : toUpdate) {
+            world.entityJoinedWorld(entity, false);
+        }
+        // Paper end
+
+        nbttagcompound.set("Entities", nbttaglist1);
+        NBTTagList nbttaglist2 = new NBTTagList();
+
+        iterator = chunk.getTileEntities().values().iterator();
+
+        while (iterator.hasNext()) {
+            TileEntity tileentity = (TileEntity) iterator.next();
+
+            nbttagcompound1 = tileentity.save(new NBTTagCompound());
+            nbttaglist2.add(nbttagcompound1);
+        }
+
+        nbttagcompound.set("TileEntities", nbttaglist2);
+        List list = world.a(chunk, false);
+
+        if (list != null) {
+            long k = world.getTime();
+            NBTTagList nbttaglist3 = new NBTTagList();
+            Iterator iterator1 = list.iterator();
+
+            while (iterator1.hasNext()) {
+                NextTickListEntry nextticklistentry = (NextTickListEntry) iterator1.next();
+                NBTTagCompound nbttagcompound2 = new NBTTagCompound();
+                MinecraftKey minecraftkey = (MinecraftKey) Block.REGISTRY.b(nextticklistentry.a());
+
+                nbttagcompound2.setString("i", minecraftkey == null ? "" : minecraftkey.toString());
+                nbttagcompound2.setInt("x", nextticklistentry.a.getX());
+                nbttagcompound2.setInt("y", nextticklistentry.a.getY());
+                nbttagcompound2.setInt("z", nextticklistentry.a.getZ());
+                nbttagcompound2.setInt("t", (int) (nextticklistentry.b - k));
+                nbttagcompound2.setInt("p", nextticklistentry.c);
+                nbttaglist3.add(nbttagcompound2);
+            }
+
+            nbttagcompound.set("TileTicks", nbttaglist3);
+        }
+
+    }
+
+    private Chunk a(World world, NBTTagCompound nbttagcompound) {
+        int i = nbttagcompound.getInt("xPos");
+        int j = nbttagcompound.getInt("zPos");
+        Chunk chunk = new Chunk(world, i, j);
+
+        chunk.a(nbttagcompound.getIntArray("HeightMap"));
+        chunk.d(nbttagcompound.getBoolean("TerrainPopulated"));
+        chunk.e(nbttagcompound.getBoolean("LightPopulated"));
+        chunk.c(nbttagcompound.getLong("InhabitedTime"));
+        NBTTagList nbttaglist = nbttagcompound.getList("Sections", 10);
+        boolean flag = true;
+        ChunkSection[] achunksection = new ChunkSection[16];
+        boolean flag1 = world.worldProvider.m();
+
+        for (int k = 0; k < nbttaglist.size(); ++k) {
+            NBTTagCompound nbttagcompound1 = nbttaglist.get(k);
+            byte b0 = nbttagcompound1.getByte("Y");
+            ChunkSection chunksection = new ChunkSection(b0 << 4, flag1, world.chunkPacketBlockController.getPredefinedBlockData(chunk, b0)); // Paper - Anti-Xray - Add predefined block data
+            byte[] abyte = nbttagcompound1.getByteArray("Blocks");
+            NibbleArray nibblearray = new NibbleArray(nbttagcompound1.getByteArray("Data"));
+            NibbleArray nibblearray1 = nbttagcompound1.hasKeyOfType("Add", 7) ? new NibbleArray(nbttagcompound1.getByteArray("Add")) : null;
+
+            chunksection.getBlocks().a(abyte, nibblearray, nibblearray1);
+            chunksection.a(new NibbleArray(nbttagcompound1.getByteArray("BlockLight")));
+            if (flag1) {
+                chunksection.b(new NibbleArray(nbttagcompound1.getByteArray("SkyLight")));
+            }
+
+            chunksection.recalcBlockCounts();
+            achunksection[b0] = chunksection;
+        }
+
+        chunk.a(achunksection);
+        if (nbttagcompound.hasKeyOfType("Biomes", 7)) {
+            chunk.a(nbttagcompound.getByteArray("Biomes"));
+        }
+
+        // CraftBukkit start - End this method here and split off entity loading to another method
+        return chunk;
+    }
+
+    public void loadEntities(Chunk chunk, NBTTagCompound nbttagcompound, World world) {
+        // CraftBukkit end
+        world.timings.syncChunkLoadNBTTimer.startTiming(); // Spigot
+        NBTTagList nbttaglist1 = nbttagcompound.getList("Entities", 10);
+
+        for (int l = 0; l < nbttaglist1.size(); ++l) {
+            NBTTagCompound nbttagcompound2 = nbttaglist1.get(l);
+
+            a(nbttagcompound2, world, chunk);
+            chunk.g(true);
+        }
+        NBTTagList nbttaglist2 = nbttagcompound.getList("TileEntities", 10);
+
+        for (int i1 = 0; i1 < nbttaglist2.size(); ++i1) {
+            NBTTagCompound nbttagcompound3 = nbttaglist2.get(i1);
+            TileEntity tileentity = TileEntity.create(world, nbttagcompound3);
+
+            if (tileentity != null) {
+                chunk.a(tileentity);
+            }
+        }
+
+        if (nbttagcompound.hasKeyOfType("TileTicks", 9)) {
+            NBTTagList nbttaglist3 = nbttagcompound.getList("TileTicks", 10);
+
+            for (int j1 = 0; j1 < nbttaglist3.size(); ++j1) {
+                NBTTagCompound nbttagcompound4 = nbttaglist3.get(j1);
+                Block block;
+
+                if (nbttagcompound4.hasKeyOfType("i", 8)) {
+                    block = Block.getByName(nbttagcompound4.getString("i"));
+                } else {
+                    block = Block.getById(nbttagcompound4.getInt("i"));
+                }
+
+                world.b(new BlockPosition(nbttagcompound4.getInt("x"), nbttagcompound4.getInt("y"), nbttagcompound4.getInt("z")), block, nbttagcompound4.getInt("t"), nbttagcompound4.getInt("p"));
+            }
+        }
+        world.timings.syncChunkLoadNBTTimer.stopTiming(); // Spigot
+
+        // return chunk; // CraftBukkit
+    }
+
+    @Nullable
+    public static Entity a(NBTTagCompound nbttagcompound, World world, Chunk chunk) {
+        Entity entity = a(nbttagcompound, world);
+
+        if (entity == null) {
+            return null;
+        } else {
+            chunk.a(entity);
+            if (nbttagcompound.hasKeyOfType("Passengers", 9)) {
+                NBTTagList nbttaglist = nbttagcompound.getList("Passengers", 10);
+
+                for (int i = 0; i < nbttaglist.size(); ++i) {
+                    Entity entity1 = a(nbttaglist.get(i), world, chunk);
+
+                    if (entity1 != null) {
+                        entity1.a(entity, true);
+                    }
+                }
+            }
+
+            return entity;
+        }
+    }
+
+    @Nullable
+    // CraftBukkit start
+    public static Entity a(NBTTagCompound nbttagcompound, World world, double d0, double d1, double d2, boolean flag) {
+        return spawnEntity(nbttagcompound, world, d0, d1, d2, flag, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT);
+    }
+
+    public static Entity spawnEntity(NBTTagCompound nbttagcompound, World world, double d0, double d1, double d2, boolean flag, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason spawnReason) {
+        // CraftBukkit end
+        Entity entity = a(nbttagcompound, world);
+
+        if (entity == null) {
+            return null;
+        } else {
+            entity.setPositionRotation(d0, d1, d2, entity.yaw, entity.pitch);
+            if (flag && !world.addEntity(entity, spawnReason)) { // CraftBukkit
+                return null;
+            } else {
+                if (nbttagcompound.hasKeyOfType("Passengers", 9)) {
+                    NBTTagList nbttaglist = nbttagcompound.getList("Passengers", 10);
+
+                    for (int i = 0; i < nbttaglist.size(); ++i) {
+                        Entity entity1 = a(nbttaglist.get(i), world, d0, d1, d2, flag);
+
+                        if (entity1 != null) {
+                            entity1.a(entity, true);
+                        }
+                    }
+                }
+
+                return entity;
+            }
+        }
+    }
+
+    @Nullable
+    protected static Entity a(NBTTagCompound nbttagcompound, World world) {
+        try {
+            return EntityTypes.a(nbttagcompound, world);
+        } catch (RuntimeException runtimeexception) {
+            return null;
+        }
+    }
+
+    // CraftBukkit start
+    public static void a(Entity entity, World world) {
+        a(entity, world, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT);
+    }
+
+    public static void a(Entity entity, World world, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason reason) {
+        if (!entity.valid && world.addEntity(entity, reason) && entity.isVehicle()) { // Paper
+            // CraftBukkit end
+            Iterator iterator = entity.bF().iterator();
+
+            while (iterator.hasNext()) {
+                Entity entity1 = (Entity) iterator.next();
+
+                a(entity1, world);
+            }
+        }
+
+    }
+
+    @Nullable
+    public static Entity a(NBTTagCompound nbttagcompound, World world, boolean flag) {
+        Entity entity = a(nbttagcompound, world);
+
+        if (entity == null) {
+            return null;
+        } else if (flag && !world.addEntity(entity)) {
+            return null;
+        } else {
+            if (nbttagcompound.hasKeyOfType("Passengers", 9)) {
+                NBTTagList nbttaglist = nbttagcompound.getList("Passengers", 10);
+
+                for (int i = 0; i < nbttaglist.size(); ++i) {
+                    Entity entity1 = a(nbttaglist.get(i), world, flag);
+
+                    if (entity1 != null) {
+                        entity1.a(entity, true);
+                    }
+                }
+            }
+
+            return entity;
+        }
+    }
+
+    // Paper start - Chunk queue improvements
+    private static class QueuedChunk {
+        public ChunkCoordIntPair coords;
+        public Supplier<NBTTagCompound> compoundSupplier;
+
+        public QueuedChunk(ChunkCoordIntPair coords, Supplier<NBTTagCompound> compoundSupplier) {
+            this.coords = coords;
+            this.compoundSupplier = compoundSupplier;
+        }
+    }
+    // Paper end
+}

sources/src/main/java/net/minecraft/server/EnchantmentManager.java

@@ -11,10 +11,8 @@ import java.util.Random;
 import java.util.Map.Entry;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Expose private members<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Expose private members (cause mixin errors)
  */
 public class EnchantmentManager {
 

sources/src/main/java/net/minecraft/server/EntityPlayer.java

@@ -2,6 +2,7 @@ package net.minecraft.server;
 
 import com.google.common.collect.Lists;
 import com.mojang.authlib.GameProfile;
+
 import io.netty.buffer.Unpooled;
 import java.util.ArrayDeque; // Paper
 import java.util.ArrayList;
@@ -31,10 +32,8 @@ import org.bukkit.inventory.MainHand;
 // CraftBukkit end
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add volatile to fields<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 2) Add lock to player track (safety issue)
  */
 public class EntityPlayer extends EntityHuman implements ICrafting {
 
@@ -745,7 +744,9 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
         if (entity instanceof EntityPlayer) {
             WorldServer worldServer = (WorldServer) entity.getWorld();
             worldServer.tracker.untrackEntity(this);
+            worldServer.tracker.entriesLock.writeLock().lock(); // Akarin - ProtocolSupport will overwrite track method
             worldServer.tracker.track(this);
+            worldServer.tracker.entriesLock.writeLock().unlock(); // Akarin - ProtocolSupport will overwrite track method
         }
         // Paper end
 
@@ -1420,8 +1421,8 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
     }
 
     // CraftBukkit start - Add per-player time and weather.
-    public volatile long timeOffset = 0; // Akarin - volatile
-    public volatile boolean relativeTime = true; // Akarin - volatile
+    public long timeOffset = 0;
+    public boolean relativeTime = true;
 
     public long getPlayerTime() {
         if (this.relativeTime) {

sources/src/main/java/net/minecraft/server/EntityTracker.java

@@ -2,28 +2,28 @@ package net.minecraft.server;
 
 import com.google.common.collect.Lists;
 import com.google.common.collect.Sets;
+import com.googlecode.concurentlocks.ReentrantReadWriteUpdateLock;
 
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.Set;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+import javax.annotation.concurrent.ThreadSafe;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Make entries-set concurrent<br>
- * 2) Add lock for entries-set operations<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Made collections and entry access thread-safe (safety issue)
  */
+@ThreadSafe // Akarin
 public class EntityTracker {
 
     private static final Logger a = LogManager.getLogger();
     private final WorldServer world;
-    private final Set<EntityTrackerEntry> c = Sets.newConcurrentHashSet(); // Akarin - make concurrent
-    private final ReentrantReadWriteLock entriesLock = new ReentrantReadWriteLock(); // Akarin - add lock
+    private final Set<EntityTrackerEntry> c = Sets.newHashSet();
+    public final ReentrantReadWriteUpdateLock entriesLock = new ReentrantReadWriteUpdateLock(); // Akarin - add lock
     public final IntHashMap<EntityTrackerEntry> trackedEntities = new IntHashMap();
     private int e;
 
@@ -40,8 +40,8 @@ public class EntityTracker {
         if (entity instanceof EntityPlayer) {
             this.addEntity(entity, 512, 2);
             EntityPlayer entityplayer = (EntityPlayer) entity;
-            entriesLock.readLock().lock(); // Akarin
             Iterator iterator = this.c.iterator();
+            // entriesLock.writeLock().lock(); // Akarin - locked in EntityPlayer
 
             while (iterator.hasNext()) {
                 EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();
@@ -50,7 +50,7 @@ public class EntityTracker {
                     entitytrackerentry.updatePlayer(entityplayer);
                 }
             }
-            entriesLock.readLock().unlock(); // Akarin
+            // entriesLock.writeLock().unlock(); // Akarin - locked in EntityPlayer
         } else if (entity instanceof EntityFishingHook) {
             this.addEntity(entity, 64, 5, true);
         } else if (entity instanceof EntityArrow) {
@@ -121,18 +121,18 @@ public class EntityTracker {
         org.spigotmc.AsyncCatcher.catchOp( "entity track"); // Spigot
         i = org.spigotmc.TrackingRange.getEntityTrackingRange(entity, i); // Spigot
         try {
+            // entriesLock.writeLock().lock(); // Akarin - locked from track method
             if (this.trackedEntities.b(entity.getId())) {
                 throw new IllegalStateException("Entity is already tracked!");
             }
 
             EntityTrackerEntry entitytrackerentry = new EntityTrackerEntry(entity, i, this.e, j, flag);
 
-            entriesLock.writeLock().lock(); // Akarin
             this.c.add(entitytrackerentry);
-            entriesLock.writeLock().unlock(); // Akarin
 
             this.trackedEntities.a(entity.getId(), entitytrackerentry);
             entitytrackerentry.scanPlayers(this.world.players);
+            // entriesLock.writeLock().unlock(); // Akarin - locked from track method
         } catch (Throwable throwable) {
             CrashReport crashreport = CrashReport.a(throwable, "Adding entity to track");
             CrashReportSystemDetails crashreportsystemdetails = crashreport.a("Entity To Track");
@@ -192,9 +192,9 @@ public class EntityTracker {
 
     public void updatePlayers() {
         ArrayList arraylist = Lists.newArrayList();
-        entriesLock.readLock().lock(); // Akarin
         Iterator iterator = this.c.iterator();
         world.timings.tracker1.startTiming(); // Spigot
+        entriesLock.writeLock().lock(); // Akarin
         while (iterator.hasNext()) {
             EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();
 
@@ -207,7 +207,6 @@ public class EntityTracker {
                 }
             }
         }
-        entriesLock.readLock().unlock(); // Akarin
         world.timings.tracker1.stopTiming(); // Spigot
 
         world.timings.tracker2.startTiming(); // Spigot
@@ -223,13 +222,14 @@ public class EntityTracker {
                 }
             }
         }
+        entriesLock.writeLock().unlock(); // Akarin
         world.timings.tracker2.stopTiming(); // Spigot
 
     }
 
     public void a(EntityPlayer entityplayer) {
-        entriesLock.readLock().lock(); // Akarin
         Iterator iterator = this.c.iterator();
+        entriesLock.writeLock().lock(); // Akarin
 
         while (iterator.hasNext()) {
             EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();
@@ -240,11 +240,13 @@ public class EntityTracker {
                 entitytrackerentry.updatePlayer(entityplayer);
             }
         }
-        entriesLock.readLock().unlock(); // Akarin
+        entriesLock.writeLock().unlock(); // Akarin
     }
 
     public void a(Entity entity, Packet<?> packet) {
+        entriesLock.readLock().lock(); // Akarin
         EntityTrackerEntry entitytrackerentry = this.trackedEntities.get(entity.getId());
+        entriesLock.readLock().unlock(); // Akarin
 
         if (entitytrackerentry != null) {
             entitytrackerentry.broadcast(packet);
@@ -253,7 +255,9 @@ public class EntityTracker {
     }
 
     public void sendPacketToEntity(Entity entity, Packet<?> packet) {
+        entriesLock.readLock().lock(); // Akarin
         EntityTrackerEntry entitytrackerentry = this.trackedEntities.get(entity.getId());
+        entriesLock.readLock().unlock(); // Akarin
 
         if (entitytrackerentry != null) {
             entitytrackerentry.broadcastIncludingSelf(packet);
@@ -262,22 +266,22 @@ public class EntityTracker {
     }
 
     public void untrackPlayer(EntityPlayer entityplayer) {
-        entriesLock.readLock().lock(); // Akarin
         Iterator iterator = this.c.iterator();
+        entriesLock.writeLock().lock();
 
         while (iterator.hasNext()) {
             EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();
 
             entitytrackerentry.clear(entityplayer);
         }
-        entriesLock.readLock().unlock(); // Akarin
+        entriesLock.writeLock().unlock();
     }
 
     public void a(EntityPlayer entityplayer, Chunk chunk) {
         ArrayList arraylist = Lists.newArrayList();
         ArrayList arraylist1 = Lists.newArrayList();
-        entriesLock.readLock().lock(); // Akarin
         Iterator iterator = this.c.iterator();
+        entriesLock.writeLock().lock(); // Akarin
 
         while (iterator.hasNext()) {
             EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();
@@ -294,7 +298,7 @@ public class EntityTracker {
                 }
             }
         }
-        entriesLock.readLock().unlock(); // Akarin
+        entriesLock.writeLock().unlock(); // Akarin
 
         Entity entity1;
 
@@ -320,8 +324,8 @@ public class EntityTracker {
 
     public void a(int i) {
         this.e = (i - 1) * 16;
-        entriesLock.readLock().lock(); // Akarin
         Iterator iterator = this.c.iterator();
+        entriesLock.readLock().lock(); // Akarin
 
         while (iterator.hasNext()) {
             EntityTrackerEntry entitytrackerentry = (EntityTrackerEntry) iterator.next();

sources/src/main/java/net/minecraft/server/EnumDirection.java

@@ -10,10 +10,8 @@ import java.util.Random;
 import javax.annotation.Nullable;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add OBFHELPER<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Add OBFHELPER (panda redstone)
  */
 public enum EnumDirection implements INamable {
 

sources/src/main/java/net/minecraft/server/FileIOThread.java

@@ -0,0 +1,81 @@
+package net.minecraft.server;
+
+import java.util.List;
+
+/**
+ * Akarin Changes Note
+ * 1) Multi-threaded chunk saving (performance)
+ */
+public class FileIOThread implements Runnable {
+
+    private static final FileIOThread a = new FileIOThread();
+    private final List<IAsyncChunkSaver> b = /*Collections.synchronizedList(Lists.newArrayList())*/ null; // Akarin - I don't think any plugin rely on this
+    private volatile long c;
+    private volatile long d;
+    private volatile boolean e;
+
+    private FileIOThread() {
+        // Thread thread = new Thread(this, "File IO Thread"); // Akarin
+
+        // thread.setPriority(1); // Akarin
+        // thread.start(); // Akarin
+    }
+
+    public static FileIOThread a() {
+        return FileIOThread.a;
+    }
+
+    public void run() {
+        while (true) {
+            this.c();
+        }
+    }
+
+    private void c() {
+        for (int i = 0; i < this.b.size(); ++i) {
+            IAsyncChunkSaver iasyncchunksaver = (IAsyncChunkSaver) this.b.get(i);
+            boolean flag = iasyncchunksaver.a();
+
+            if (!flag) {
+                this.b.remove(i--);
+                ++this.d;
+            }
+
+            // Paper start - Add toggle
+            if (com.destroystokyo.paper.PaperConfig.enableFileIOThreadSleep) {
+                try {
+                    Thread.sleep(this.e ? 0L : 2L);
+                } catch (InterruptedException interruptedexception) {
+                    interruptedexception.printStackTrace();
+                }
+            }
+            // Paper end
+        }
+
+        if (this.b.isEmpty()) {
+            try {
+                Thread.sleep(25L);
+            } catch (InterruptedException interruptedexception1) {
+                interruptedexception1.printStackTrace();
+            }
+        }
+
+    }
+
+    public void a(IAsyncChunkSaver iasyncchunksaver) {
+        if (!this.b.contains(iasyncchunksaver)) {
+            ++this.c;
+            this.b.add(iasyncchunksaver);
+        }
+    }
+
+    public void b() throws InterruptedException {
+        this.e = true;
+
+        while (this.c != this.d) {
+            Thread.sleep(10L);
+        }
+
+        this.e = false;
+    }
+}

sources/src/main/java/net/minecraft/server/ItemEnderEye.java

@@ -3,10 +3,8 @@ package net.minecraft.server;
 import io.akarin.server.core.AkarinGlobalConfig;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add end portal disable feature<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Add end portal disable feature (feature)
  */
 public class ItemEnderEye extends Item {
 

sources/src/main/java/net/minecraft/server/ItemMonsterEgg.java

@@ -0,0 +1,243 @@
+package net.minecraft.server;
+
+import java.util.Iterator;
+import java.util.List;
+import java.util.UUID;
+import javax.annotation.Nullable;
+
+import io.akarin.server.core.AkarinGlobalConfig;
+
+/**
+ * Akarin Changes Note
+ * 1) Restricted spawner modify (feature)
+ */
+public class ItemMonsterEgg extends Item {
+
+    public ItemMonsterEgg() {
+        this.b(CreativeModeTab.f);
+    }
+
+    public String b(ItemStack itemstack) {
+        String s = ("" + LocaleI18n.get(this.getName() + ".name")).trim();
+        String s1 = EntityTypes.a(h(itemstack));
+
+        if (s1 != null) {
+            s = s + " " + LocaleI18n.get("entity." + s1 + ".name");
+        }
+
+        return s;
+    }
+
+    public EnumInteractionResult a(EntityHuman entityhuman, World world, BlockPosition blockposition, EnumHand enumhand, EnumDirection enumdirection, float f, float f1, float f2) {
+        ItemStack itemstack = entityhuman.b(enumhand);
+
+        if (world.isClientSide) {
+            return EnumInteractionResult.SUCCESS;
+        } else if (!entityhuman.a(blockposition.shift(enumdirection), enumdirection, itemstack)) {
+            return EnumInteractionResult.FAIL;
+        } else {
+            IBlockData iblockdata = world.getType(blockposition);
+            Block block = iblockdata.getBlock();
+
+            if (block == Blocks.MOB_SPAWNER && (AkarinGlobalConfig.allowSpawnerModify || entityhuman.isCreativeAndOp())) { // Akarin
+                TileEntity tileentity = world.getTileEntity(blockposition);
+
+                if (tileentity instanceof TileEntityMobSpawner) {
+                    MobSpawnerAbstract mobspawnerabstract = ((TileEntityMobSpawner) tileentity).getSpawner();
+
+                    mobspawnerabstract.setMobName(h(itemstack));
+                    tileentity.update();
+                    world.notify(blockposition, iblockdata, iblockdata, 3);
+                    if (!entityhuman.abilities.canInstantlyBuild) {
+                        itemstack.subtract(1);
+                    }
+
+                    return EnumInteractionResult.SUCCESS;
+                }
+            }
+
+            BlockPosition blockposition1 = blockposition.shift(enumdirection);
+            double d0 = this.a(world, blockposition1);
+            Entity entity = a(world, h(itemstack), (double) blockposition1.getX() + 0.5D, (double) blockposition1.getY() + d0, (double) blockposition1.getZ() + 0.5D);
+
+            if (entity != null) {
+                if (entity instanceof EntityLiving && itemstack.hasName()) {
+                    entity.setCustomName(itemstack.getName());
+                }
+
+                a(world, entityhuman, itemstack, entity);
+                if (!entityhuman.abilities.canInstantlyBuild) {
+                    itemstack.subtract(1);
+                }
+            }
+
+            return EnumInteractionResult.SUCCESS;
+        }
+    }
+
+    protected double a(World world, BlockPosition blockposition) {
+        AxisAlignedBB axisalignedbb = (new AxisAlignedBB(blockposition)).b(0.0D, -1.0D, 0.0D);
+        List list = world.getCubes((Entity) null, axisalignedbb);
+
+        if (list.isEmpty()) {
+            return 0.0D;
+        } else {
+            double d0 = axisalignedbb.b;
+
+            AxisAlignedBB axisalignedbb1;
+
+            for (Iterator iterator = list.iterator(); iterator.hasNext(); d0 = Math.max(axisalignedbb1.e, d0)) {
+                axisalignedbb1 = (AxisAlignedBB) iterator.next();
+            }
+
+            return d0 - (double) blockposition.getY();
+        }
+    }
+
+    public static void a(World world, @Nullable EntityHuman entityhuman, ItemStack itemstack, @Nullable Entity entity) {
+        MinecraftServer minecraftserver = world.getMinecraftServer();
+
+        if (minecraftserver != null && entity != null) {
+            NBTTagCompound nbttagcompound = itemstack.getTag();
+
+            if (nbttagcompound != null && nbttagcompound.hasKeyOfType("EntityTag", 10)) {
+                if (!world.isClientSide && entity.bC() && (entityhuman == null || !minecraftserver.getPlayerList().isOp(entityhuman.getProfile()))) {
+                    return;
+                }
+
+                NBTTagCompound nbttagcompound1 = entity.save(new NBTTagCompound());
+                UUID uuid = entity.getUniqueID();
+
+                nbttagcompound1.a(nbttagcompound.getCompound("EntityTag"));
+                entity.a(uuid);
+                entity.f(nbttagcompound1);
+            }
+
+        }
+    }
+
+    public InteractionResultWrapper<ItemStack> a(World world, EntityHuman entityhuman, EnumHand enumhand) {
+        ItemStack itemstack = entityhuman.b(enumhand);
+
+        if (world.isClientSide) {
+            return new InteractionResultWrapper(EnumInteractionResult.PASS, itemstack);
+        } else {
+            MovingObjectPosition movingobjectposition = this.a(world, entityhuman, true);
+
+            if (movingobjectposition != null && movingobjectposition.type == MovingObjectPosition.EnumMovingObjectType.BLOCK) {
+                BlockPosition blockposition = movingobjectposition.a();
+
+                if (!(world.getType(blockposition).getBlock() instanceof BlockFluids)) {
+                    return new InteractionResultWrapper(EnumInteractionResult.PASS, itemstack);
+                } else if (world.a(entityhuman, blockposition) && entityhuman.a(blockposition, movingobjectposition.direction, itemstack)) {
+                    Entity entity = a(world, h(itemstack), (double) blockposition.getX() + 0.5D, (double) blockposition.getY() + 0.5D, (double) blockposition.getZ() + 0.5D);
+
+                    if (entity == null) {
+                        return new InteractionResultWrapper(EnumInteractionResult.PASS, itemstack);
+                    } else {
+                        if (entity instanceof EntityLiving && itemstack.hasName()) {
+                            entity.setCustomName(itemstack.getName());
+                        }
+
+                        a(world, entityhuman, itemstack, entity);
+                        if (!entityhuman.abilities.canInstantlyBuild) {
+                            itemstack.subtract(1);
+                        }
+
+                        entityhuman.b(StatisticList.b((Item) this));
+                        return new InteractionResultWrapper(EnumInteractionResult.SUCCESS, itemstack);
+                    }
+                } else {
+                    return new InteractionResultWrapper(EnumInteractionResult.FAIL, itemstack);
+                }
+            } else {
+                return new InteractionResultWrapper(EnumInteractionResult.PASS, itemstack);
+            }
+        }
+    }
+
+    @Nullable
+    public static Entity a(World world, @Nullable MinecraftKey minecraftkey, double d0, double d1, double d2) {
+        return spawnCreature(world, minecraftkey, d0, d1, d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER_EGG);
+    }
+
+    @Nullable
+    public static Entity spawnCreature(World world, @Nullable MinecraftKey minecraftkey, double d0, double d1, double d2, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason spawnReason) {
+        if (minecraftkey != null && EntityTypes.eggInfo.containsKey(minecraftkey)) {
+            Entity entity = null;
+
+            for (int i = 0; i < 1; ++i) {
+                entity = EntityTypes.a(minecraftkey, world);
+                if (entity instanceof EntityInsentient) {
+                    EntityInsentient entityinsentient = (EntityInsentient) entity;
+
+                    entity.setPositionRotation(d0, d1, d2, MathHelper.g(world.random.nextFloat() * 360.0F), 0.0F);
+                    entityinsentient.aP = entityinsentient.yaw;
+                    entityinsentient.aN = entityinsentient.yaw;
+                    entityinsentient.prepare(world.D(new BlockPosition(entityinsentient)), (GroupDataEntity) null);
+                    // CraftBukkit start - don't return an entity when CreatureSpawnEvent is canceled
+                    if (!world.addEntity(entity, spawnReason)) {
+                        entity = null;
+                    } else {
+                        entityinsentient.D();
+                    }
+                    // CraftBukkit end
+                }
+            }
+
+            return entity;
+        } else {
+            return null;
+        }
+    }
+
+    public void a(CreativeModeTab creativemodetab, NonNullList<ItemStack> nonnulllist) {
+        if (this.a(creativemodetab)) {
+            Iterator iterator = EntityTypes.eggInfo.values().iterator();
+
+            while (iterator.hasNext()) {
+                EntityTypes.MonsterEggInfo entitytypes_monsteregginfo = (EntityTypes.MonsterEggInfo) iterator.next();
+                ItemStack itemstack = new ItemStack(this, 1);
+
+                a(itemstack, entitytypes_monsteregginfo.a);
+                nonnulllist.add(itemstack);
+            }
+        }
+
+    }
+
+    public static void a(ItemStack itemstack, MinecraftKey minecraftkey) {
+        NBTTagCompound nbttagcompound = itemstack.hasTag() ? itemstack.getTag() : new NBTTagCompound();
+        NBTTagCompound nbttagcompound1 = new NBTTagCompound();
+
+        nbttagcompound1.setString("id", minecraftkey.toString());
+        nbttagcompound.set("EntityTag", nbttagcompound1);
+        itemstack.setTag(nbttagcompound);
+    }
+
+    @Nullable
+    public static MinecraftKey h(ItemStack itemstack) {
+        NBTTagCompound nbttagcompound = itemstack.getTag();
+
+        if (nbttagcompound == null) {
+            return null;
+        } else if (!nbttagcompound.hasKeyOfType("EntityTag", 10)) {
+            return null;
+        } else {
+            NBTTagCompound nbttagcompound1 = nbttagcompound.getCompound("EntityTag");
+
+            if (!nbttagcompound1.hasKeyOfType("id", 8)) {
+                return null;
+            } else {
+                String s = nbttagcompound1.getString("id");
+                MinecraftKey minecraftkey = new MinecraftKey(s);
+
+                if (!s.contains(":")) {
+                    nbttagcompound1.setString("id", minecraftkey.toString());
+                }
+
+                return minecraftkey;
+            }
+        }
+    }
+}

sources/src/main/java/net/minecraft/server/NetworkManager.java

@@ -1,8 +1,9 @@
 package net.minecraft.server;
 
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.googlecode.concurentlocks.ReentrantReadWriteUpdateLock;
 
-import io.akarin.api.internal.collections.CheckedConcurrentLinkedQueue;
+import io.akarin.api.internal.utils.CheckedConcurrentLinkedQueue;
 import io.netty.channel.Channel;
 import io.netty.channel.ChannelFuture;
 import io.netty.channel.ChannelFutureListener;
@@ -20,7 +21,6 @@ import io.netty.util.concurrent.GenericFutureListener;
 
 import java.net.SocketAddress;
 import java.util.Queue;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
 import javax.annotation.Nullable;
 import javax.crypto.SecretKey;
 import org.apache.commons.lang3.ArrayUtils;
@@ -31,11 +31,10 @@ import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add volatile to fields<br>
- * 2) Expose private members<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 2) Expose private members (nsc)
+ * 3) Changes lock type to updatable lock (compatibility)
+ * 4) Removes unneed array creation (performance)
  */
 public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
 
@@ -75,13 +74,13 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
     };
     private final EnumProtocolDirection h;
     private final Queue<NetworkManager.QueuedPacket> i = new CheckedConcurrentLinkedQueue<NetworkManager.QueuedPacket>(); private final Queue<NetworkManager.QueuedPacket> getPacketQueue() { return this.i; } // Paper - Anti-Xray - OBFHELPER // Akarin
-    private final ReentrantReadWriteLock j = new ReentrantReadWriteLock();
+    private final ReentrantReadWriteUpdateLock j = new ReentrantReadWriteUpdateLock(); // Akarin - use update lock
     public Channel channel;
     // Spigot Start // PAIL
     public SocketAddress l;
     public java.util.UUID spoofedUUID;
     public com.mojang.authlib.properties.Property[] spoofedProfile;
-    public volatile boolean preparing = true; // Akarin - add volatile
+    public boolean preparing = true;
     // Spigot End
     private PacketListener m;
     private IChatBaseComponent n;
@@ -165,7 +164,7 @@ public class NetworkManager extends SimpleChannelInboundHandler<Packet<?>> {
             this.j.writeLock().lock();
 
             try {
-                this.i.add(new NetworkManager.QueuedPacket(packet, new GenericFutureListener[0]));
+                this.i.add(new NetworkManager.QueuedPacket(packet)); // Akarin - remove fake listener creation
             } finally {
                 this.j.writeLock().unlock();
             }

sources/src/main/java/net/minecraft/server/PacketPlayOutMapChunk.java

@@ -0,0 +1,193 @@
+package net.minecraft.server;
+
+import com.google.common.collect.Lists;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map.Entry;
+
+// Paper start
+import com.destroystokyo.paper.antixray.PacketPlayOutMapChunkInfo; // Anti-Xray
+// Paper end
+
+/**
+ * Akarin Changes Note
+ * 1) WrappedByteBuf -> ByteBuf (compatibility)
+ */
+public class PacketPlayOutMapChunk implements Packet<PacketListenerPlayOut> {
+
+    private int a;
+    private int b;
+    private int c;
+    private ByteBuf d; // Akarin - byte[] -> ByteBuf
+    private List<NBTTagCompound> e;
+    private boolean f;
+    private volatile boolean ready = false; // Paper - Async-Anti-Xray - Ready flag for the network manager
+
+    // Paper start - Async-Anti-Xray - Set the ready flag to true
+    public PacketPlayOutMapChunk() {
+        this.ready = true;
+    }
+    // Paper end
+
+    public PacketPlayOutMapChunk(Chunk chunk, int i) {
+        PacketPlayOutMapChunkInfo packetPlayOutMapChunkInfo = chunk.world.chunkPacketBlockController.getPacketPlayOutMapChunkInfo(this, chunk, i); // Paper - Anti-Xray - Add chunk packet info
+        this.a = chunk.locX;
+        this.b = chunk.locZ;
+        this.f = i == '\uffff';
+        boolean flag = chunk.getWorld().worldProvider.m();
+
+        this.d = allocateBuffer(this.a(chunk, flag, i)); // Akarin
+
+        // Paper start - Anti-Xray - Add chunk packet info
+        if (packetPlayOutMapChunkInfo != null) {
+            packetPlayOutMapChunkInfo.setData(this.d);
+        }
+        // Paper end
+
+        this.c = this.writeChunk(new PacketDataSerializer(this.d), chunk, flag, i, packetPlayOutMapChunkInfo); // Paper - Anti-Xray - Add chunk packet info // Akarin
+        this.e = Lists.newArrayList();
+        Iterator iterator = chunk.getTileEntities().entrySet().iterator();
+
+        while (iterator.hasNext()) {
+            Entry entry = (Entry) iterator.next();
+            BlockPosition blockposition = (BlockPosition) entry.getKey();
+            TileEntity tileentity = (TileEntity) entry.getValue();
+            int j = blockposition.getY() >> 4;
+
+            if (this.e() || (i & 1 << j) != 0) {
+                NBTTagCompound nbttagcompound = tileentity.d();
+
+                this.e.add(nbttagcompound);
+            }
+        }
+
+        chunk.world.chunkPacketBlockController.modifyBlocks(this, packetPlayOutMapChunkInfo); // Paper - Anti-Xray - Modify blocks
+    }
+
+    // Paper start - Async-Anti-Xray - Getter and Setter for the ready flag
+    public boolean isReady() {
+        return this.ready;
+    }
+
+    public void setReady(boolean ready) {
+        this.ready = ready;
+    }
+    // Paper end
+
+    public void a(PacketDataSerializer packetdataserializer) throws IOException {
+        this.a = packetdataserializer.readInt();
+        this.b = packetdataserializer.readInt();
+        this.f = packetdataserializer.readBoolean();
+        this.c = packetdataserializer.g();
+        int i = packetdataserializer.g();
+
+        if (i > 2097152) {
+            throw new RuntimeException("Chunk Packet trying to allocate too much memory on read.");
+        } else {
+            this.d = Unpooled.buffer(i); // Akarin
+            packetdataserializer.readBytes(this.d);
+            int j = packetdataserializer.g();
+
+            this.e = Lists.newArrayList();
+
+            for (int k = 0; k < j; ++k) {
+                this.e.add(packetdataserializer.j());
+            }
+
+        }
+    }
+
+    public void b(PacketDataSerializer packetdataserializer) throws IOException {
+        packetdataserializer.writeInt(this.a);
+        packetdataserializer.writeInt(this.b);
+        packetdataserializer.writeBoolean(this.f);
+        packetdataserializer.d(this.c);
+        packetdataserializer.d(this.d.array().length); // Akarin
+        packetdataserializer.writeBytes(this.d.array()); // Akarin
+        packetdataserializer.d(this.e.size());
+        Iterator iterator = this.e.iterator();
+
+        while (iterator.hasNext()) {
+            NBTTagCompound nbttagcompound = (NBTTagCompound) iterator.next();
+
+            packetdataserializer.a(nbttagcompound);
+        }
+
+    }
+
+    public void a(PacketListenerPlayOut packetlistenerplayout) {
+        packetlistenerplayout.a(this);
+    }
+
+    private ByteBuf allocateBuffer(int expectedCapacity) { return g(expectedCapacity); } // Akarin - OBFHELPER
+    private ByteBuf g(int expectedCapacity) { // Akarin - added argument
+        ByteBuf bytebuf = Unpooled.buffer(expectedCapacity); // Akarin
+
+        bytebuf.writerIndex(0);
+        return bytebuf;
+    }
+
+    // Paper start - Anti-Xray - Support default method
+    public int writeChunk(PacketDataSerializer packetDataSerializer, Chunk chunk, boolean writeSkyLightArray, int chunkSectionSelector) { return this.a(packetDataSerializer, chunk, writeSkyLightArray, chunkSectionSelector); } // OBFHELPER
+    public int a(PacketDataSerializer packetdataserializer, Chunk chunk, boolean flag, int i) {
+        return this.a(packetdataserializer, chunk, flag, i, null);
+    }
+    // Paper end
+
+    public int writeChunk(PacketDataSerializer packetDataSerializer, Chunk chunk, boolean writeSkyLightArray, int chunkSectionSelector, PacketPlayOutMapChunkInfo packetPlayOutMapChunkInfo) { return this.a(packetDataSerializer, chunk, writeSkyLightArray, chunkSectionSelector, packetPlayOutMapChunkInfo); } // Paper - Anti-Xray - OBFHELPER
+    public int a(PacketDataSerializer packetdataserializer, Chunk chunk, boolean flag, int i, PacketPlayOutMapChunkInfo packetPlayOutMapChunkInfo) { // Paper - Anti-Xray - Add chunk packet info
+        int j = 0;
+        ChunkSection[] achunksection = chunk.getSections();
+        int k = 0;
+
+        for (int l = achunksection.length; k < l; ++k) {
+            ChunkSection chunksection = achunksection[k];
+
+            if (chunksection != Chunk.a && (!this.e() || !chunksection.a()) && (i & 1 << k) != 0) {
+                j |= 1 << k;
+                chunksection.getBlocks().writeBlocks(packetdataserializer, packetPlayOutMapChunkInfo, k); // Paper - Anti-Xray - Add chunk packet info
+                packetdataserializer.writeBytes(chunksection.getEmittedLightArray().asBytes());
+                if (flag) {
+                    packetdataserializer.writeBytes(chunksection.getSkyLightArray().asBytes());
+                }
+            }
+        }
+
+        if (this.e()) {
+            packetdataserializer.writeBytes(chunk.getBiomeIndex());
+        }
+
+        return j;
+    }
+
+    protected int a(Chunk chunk, boolean flag, int i) {
+        int j = 0;
+        ChunkSection[] achunksection = chunk.getSections();
+        int k = 0;
+
+        for (int l = achunksection.length; k < l; ++k) {
+            ChunkSection chunksection = achunksection[k];
+
+            if (chunksection != Chunk.a && (!this.e() || !chunksection.a()) && (i & 1 << k) != 0) {
+                j += chunksection.getBlocks().a();
+                j += chunksection.getEmittedLightArray().asBytes().length;
+                if (flag) {
+                    j += chunksection.getSkyLightArray().asBytes().length;
+                }
+            }
+        }
+
+        if (this.e()) {
+            j += chunk.getBiomeIndex().length;
+        }
+
+        return j;
+    }
+
+    public boolean e() {
+        return this.f;
+    }
+}

sources/src/main/java/net/minecraft/server/PaperLightingQueue.java

@@ -1,98 +0,0 @@
-package net.minecraft.server;
-
-import co.aikar.timings.Timing;
-import it.unimi.dsi.fastutil.objects.ObjectCollection;
-
-import java.util.ArrayDeque;
-
-/**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Expose private members<br>
- * @author cakoyo
- */
-class PaperLightingQueue {
-    private static final long MAX_TIME = (long) (1000000000 / 20 * .95);
-    private static int updatesThisTick;
-
-
-    static void processQueue(long curTime) {
-        updatesThisTick = 0;
-
-        final long startTime = System.nanoTime();
-        final long maxTickTime = MAX_TIME - (startTime - curTime);
-
-        START:
-        for (World world : MinecraftServer.getServer().worlds) {
-            if (!world.paperConfig.queueLightUpdates) {
-                continue;
-            }
-
-            ObjectCollection<Chunk> loadedChunks = ((WorldServer) world).getChunkProviderServer().chunks.values();
-            for (Chunk chunk : loadedChunks.toArray(new Chunk[loadedChunks.size()])) {
-                if (chunk.lightingQueue.processQueue(startTime, maxTickTime)) {
-                    break START;
-                }
-            }
-        }
-    }
-
-    public static class LightingQueue extends ArrayDeque<Runnable> { // Akarin - public
-        final private Chunk chunk;
-
-        LightingQueue(Chunk chunk) {
-            super();
-            this.chunk = chunk;
-        }
-
-        /**
-         * Processes the lighting queue for this chunk
-         *
-         * @param startTime If start Time is 0, we will not limit execution time
-         * @param maxTickTime Maximum time to spend processing lighting updates
-         * @return true to abort processing furthur lighting updates
-         */
-        private boolean processQueue(long startTime, long maxTickTime) {
-            if (this.isEmpty()) {
-                return false;
-            }
-            try (Timing ignored = chunk.world.timings.lightingQueueTimer.startTiming()) {
-                Runnable lightUpdate;
-                while ((lightUpdate = this.poll()) != null) {
-                    lightUpdate.run();
-                    if (startTime > 0 && ++PaperLightingQueue.updatesThisTick % 10 == 0 && PaperLightingQueue.updatesThisTick > 10) {
-                        if (System.nanoTime() - startTime > maxTickTime) {
-                            return true;
-                        }
-                    }
-                }
-            }
-
-            return false;
-        }
-
-        /**
-         * Flushes lighting updates to unload the chunk
-         */
-        public void processUnload() { // Akarin - public
-            if (!chunk.world.paperConfig.queueLightUpdates) {
-                return;
-            }
-            processQueue(0, 0); // No timeout
-
-            final int radius = 1; // TODO: bitflip, why should this ever be 2?
-            for (int x = chunk.locX - radius; x <= chunk.locX + radius; ++x) {
-                for (int z = chunk.locZ - radius; z <= chunk.locZ + radius; ++z) {
-                    if (x == chunk.locX && z == chunk.locZ) {
-                        continue;
-                    }
-
-                    Chunk neighbor = MCUtil.getLoadedChunkWithoutMarkingActive(chunk.world, x, z);
-                    if (neighbor != null) {
-                        neighbor.lightingQueue.processQueue(0, 0); // No timeout
-                    }
-                }
-            }
-        }
-    }
-}

sources/src/main/java/net/minecraft/server/PlayerChunk.java

@@ -14,10 +14,8 @@ import org.bukkit.craftbukkit.chunkio.ChunkIOExecutor;
 // CraftBukkit end
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Check player list empty<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Check whether players empty (performance, MC-120780)
  */
 public class PlayerChunk {
 

sources/src/main/java/net/minecraft/server/PlayerChunkMap.java

@@ -0,0 +1,601 @@
+package net.minecraft.server;
+
+import co.aikar.timings.Timing;
+import com.google.common.base.Predicate;
+import com.google.common.collect.AbstractIterator;
+import com.google.common.collect.ComparisonChain;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Sets;
+import it.unimi.dsi.fastutil.longs.Long2ObjectMap;
+import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.ThreadSafe;
+
+// CraftBukkit start
+import java.util.LinkedList;
+// CraftBukkit end
+
+/**
+ * Akarin Changes Note
+ * 1) Make whole class thread-safe (safety issue)
+ */
+@ThreadSafe // Akarin - idk why we need do so!!
+public class PlayerChunkMap {
+
+    private static final Predicate<EntityPlayer> a = new Predicate() {
+        public boolean a(@Nullable EntityPlayer entityplayer) {
+            return entityplayer != null && !entityplayer.isSpectator();
+        }
+
+        public boolean apply(@Nullable Object object) {
+            return this.a((EntityPlayer) object);
+        }
+    };
+    private static final Predicate<EntityPlayer> b = new Predicate() {
+        public boolean a(@Nullable EntityPlayer entityplayer) {
+            return entityplayer != null && (!entityplayer.isSpectator() || entityplayer.x().getGameRules().getBoolean("spectatorsGenerateChunks"));
+        }
+
+        public boolean apply(@Nullable Object object) {
+            return this.a((EntityPlayer) object);
+        }
+    };
+    private final WorldServer world;
+    private final List<EntityPlayer> managedPlayers = Lists.newArrayList();
+    private final ReentrantReadWriteLock managedPlayersLock = new ReentrantReadWriteLock(); // Akarin - add lock
+    private final Long2ObjectMap<PlayerChunk> e = new Long2ObjectOpenHashMap(4096);
+    private final Set<PlayerChunk> f = Sets.newHashSet();
+    private final List<PlayerChunk> g = Lists.newLinkedList();
+    private final List<PlayerChunk> h = Lists.newLinkedList();
+    private final List<PlayerChunk> i = Lists.newCopyOnWriteArrayList(); // Akarin - bad plugin will access this
+    private int j; public int getViewDistance() { return j; } // Paper OBFHELPER
+    private long k;
+    private boolean l = true;
+    private boolean m = true;
+    private boolean wasNotEmpty; // CraftBukkit - add field
+
+    public PlayerChunkMap(WorldServer worldserver) {
+        this.world = worldserver;
+        this.a(worldserver.spigotConfig.viewDistance); // Spigot
+    }
+
+    public WorldServer getWorld() {
+        return this.world;
+    }
+
+    public Iterator<Chunk> b() {
+        final Iterator iterator = this.i.iterator();
+
+        return new AbstractIterator<Chunk>() {
+            protected Chunk a() {
+                while (true) {
+                    if (iterator.hasNext()) {
+                        PlayerChunk playerchunk = (PlayerChunk) iterator.next();
+                        Chunk chunk = playerchunk.f();
+
+                        if (chunk == null) {
+                            continue;
+                        }
+
+                        if (!chunk.v() && chunk.isDone()) {
+                            return chunk;
+                        }
+
+                        if (!chunk.j()) {
+                            return chunk;
+                        }
+
+                        if (!playerchunk.a(128.0D, PlayerChunkMap.a)) {
+                            continue;
+                        }
+
+                        return chunk;
+                    }
+
+                    return (Chunk) this.endOfData();
+                }
+            }
+
+            protected Chunk computeNext() {
+                return this.a();
+            }
+        };
+    }
+
+    public synchronized void flush() { // Akarin - synchronized
+        long i = this.world.getTime();
+        int j;
+        PlayerChunk playerchunk;
+
+        if (i - this.k > 8000L) {
+            try (Timing ignored = world.timings.doChunkMapUpdate.startTiming()) { // Paper
+            this.k = i;
+
+            for (j = 0; j < this.i.size(); ++j) {
+                playerchunk = (PlayerChunk) this.i.get(j);
+                playerchunk.d();
+                playerchunk.c();
+            }
+            } // Paper timing
+        }
+
+        if (!this.f.isEmpty()) {
+            try (Timing ignored = world.timings.doChunkMapToUpdate.startTiming()) { // Paper
+            Iterator iterator = this.f.iterator();
+
+            while (iterator.hasNext()) {
+                playerchunk = (PlayerChunk) iterator.next();
+                playerchunk.d();
+            }
+
+            this.f.clear();
+            } // Paper timing
+        }
+
+        if (this.l && i % 4L == 0L) {
+            this.l = false;
+            try (Timing ignored = world.timings.doChunkMapSortMissing.startTiming()) { // Paper
+            Collections.sort(this.h, new Comparator() {
+                public int a(PlayerChunk playerchunk, PlayerChunk playerchunk1) {
+                    return ComparisonChain.start().compare(playerchunk.g(), playerchunk1.g()).result();
+                }
+
+                public int compare(Object object, Object object1) {
+                    return this.a((PlayerChunk) object, (PlayerChunk) object1);
+                }
+            });
+            } // Paper timing
+        }
+
+        if (this.m && i % 4L == 2L) {
+            this.m = false;
+            try (Timing ignored = world.timings.doChunkMapSortSendToPlayers.startTiming()) { // Paper
+            Collections.sort(this.g, new Comparator() {
+                public int a(PlayerChunk playerchunk, PlayerChunk playerchunk1) {
+                    return ComparisonChain.start().compare(playerchunk.g(), playerchunk1.g()).result();
+                }
+
+                public int compare(Object object, Object object1) {
+                    return this.a((PlayerChunk) object, (PlayerChunk) object1);
+                }
+            });
+            } // Paper timing
+        }
+
+        if (!this.h.isEmpty()) {
+            try (Timing ignored = world.timings.doChunkMapPlayersNeedingChunks.startTiming()) { // Paper
+            // Spigot start
+            org.spigotmc.SlackActivityAccountant activityAccountant = this.world.getMinecraftServer().slackActivityAccountant;
+            activityAccountant.startActivity(0.5);
+            int chunkGensAllowed = world.paperConfig.maxChunkGensPerTick; // Paper
+            // Spigot end
+
+            Iterator iterator1 = this.h.iterator();
+
+            while (iterator1.hasNext()) {
+                PlayerChunk playerchunk1 = (PlayerChunk) iterator1.next();
+
+                if (playerchunk1.f() == null) {
+                    boolean flag = playerchunk1.a(PlayerChunkMap.b);
+                    // Paper start
+                    if (flag && !playerchunk1.chunkExists && chunkGensAllowed-- <= 0) {
+                        continue;
+                    }
+                    // Paper end
+
+                    if (playerchunk1.a(flag)) {
+                        iterator1.remove();
+                        if (playerchunk1.b()) {
+                            this.g.remove(playerchunk1);
+                        }
+
+                        if (activityAccountant.activityTimeIsExhausted()) { // Spigot
+                            break;
+                        }
+                    }
+                // CraftBukkit start - SPIGOT-2891: remove once chunk has been provided
+                } else {
+                    iterator1.remove();
+                }
+                // CraftBukkit end
+            }
+
+            activityAccountant.endActivity(); // Spigot
+            } // Paper timing
+        }
+
+        if (!this.g.isEmpty()) {
+            j = world.paperConfig.maxChunkSendsPerTick; // Paper
+            try (Timing ignored = world.timings.doChunkMapPendingSendToPlayers.startTiming()) { // Paper
+            Iterator iterator2 = this.g.iterator();
+
+            while (iterator2.hasNext()) {
+                PlayerChunk playerchunk2 = (PlayerChunk) iterator2.next();
+
+                if (playerchunk2.b()) {
+                    iterator2.remove();
+                    --j;
+                    if (j < 0) {
+                        break;
+                    }
+                }
+            }
+            } // Paper timing
+        }
+
+        managedPlayersLock.readLock().lock(); // Akarin
+        if (this.managedPlayers.isEmpty()) {
+            try (Timing ignored = world.timings.doChunkMapUnloadChunks.startTiming()) { // Paper
+            WorldProvider worldprovider = this.world.worldProvider;
+
+            if (!worldprovider.e() && !this.world.savingDisabled) { // Paper - respect saving disabled setting
+                this.world.getChunkProviderServer().b();
+            }
+            } // Paper timing
+        }
+        managedPlayersLock.readLock().unlock(); // Akarin
+
+    }
+
+    public synchronized boolean a(int i, int j) { // Akarin - synchronized
+        long k = d(i, j);
+
+        return this.e.get(k) != null;
+    }
+
+    @Nullable
+    public synchronized PlayerChunk getChunk(int i, int j) { // Akarin - synchronized
+        return (PlayerChunk) this.e.get(d(i, j));
+    }
+
+    private PlayerChunk c(int i, int j) {
+        long k = d(i, j);
+        PlayerChunk playerchunk = (PlayerChunk) this.e.get(k);
+
+        if (playerchunk == null) {
+            playerchunk = new PlayerChunk(this, i, j);
+            this.e.put(k, playerchunk);
+            this.i.add(playerchunk);
+            if (playerchunk.f() == null) {
+                this.h.add(playerchunk);
+            }
+
+            if (!playerchunk.b()) {
+                this.g.add(playerchunk);
+            }
+        }
+
+        return playerchunk;
+    }
+
+    // CraftBukkit start - add method
+    public final boolean isChunkInUse(int x, int z) {
+        PlayerChunk pi = getChunk(x, z);
+        if (pi != null) {
+            return (pi.c.size() > 0);
+        }
+        return false;
+    }
+    // CraftBukkit end
+
+    public void flagDirty(BlockPosition blockposition) {
+        int i = blockposition.getX() >> 4;
+        int j = blockposition.getZ() >> 4;
+        PlayerChunk playerchunk = this.getChunk(i, j);
+
+        if (playerchunk != null) {
+            playerchunk.a(blockposition.getX() & 15, blockposition.getY(), blockposition.getZ() & 15);
+        }
+
+    }
+
+    public void addPlayer(EntityPlayer entityplayer) {
+        int i = (int) entityplayer.locX >> 4;
+        int j = (int) entityplayer.locZ >> 4;
+
+        entityplayer.d = entityplayer.locX;
+        entityplayer.e = entityplayer.locZ;
+
+
+        // CraftBukkit start - Load nearby chunks first
+        List<ChunkCoordIntPair> chunkList = new LinkedList<ChunkCoordIntPair>();
+
+        // Paper start - Player view distance API
+        int viewDistance = entityplayer.getViewDistance();
+        for (int k = i - viewDistance; k <= i + viewDistance; ++k) {
+            for (int l = j - viewDistance; l <= j + viewDistance; ++l) {
+                // Paper end
+                chunkList.add(new ChunkCoordIntPair(k, l));
+            }
+        }
+
+        Collections.sort(chunkList, new ChunkCoordComparator(entityplayer));
+        synchronized (this) { // Akarin - synchronized
+        for (ChunkCoordIntPair pair : chunkList) {
+            this.c(pair.x, pair.z).a(entityplayer);
+        }
+        } // Akarin
+        // CraftBukkit end
+
+        managedPlayersLock.writeLock().lock(); // Akarin
+        this.managedPlayers.add(entityplayer);
+        managedPlayersLock.writeLock().unlock(); // Akarin
+        this.e();
+    }
+
+    public void removePlayer(EntityPlayer entityplayer) {
+        int i = (int) entityplayer.d >> 4;
+        int j = (int) entityplayer.e >> 4;
+
+        // Paper start - Player view distance API
+        int viewDistance = entityplayer.getViewDistance();
+        for (int k = i - viewDistance; k <= i + viewDistance; ++k) {
+            for (int l = j - viewDistance; l <= j + viewDistance; ++l) {
+                // Paper end
+                PlayerChunk playerchunk = this.getChunk(k, l);
+
+                if (playerchunk != null) {
+                    playerchunk.b(entityplayer);
+                }
+            }
+        }
+
+        managedPlayersLock.writeLock().lock(); // Akarin
+        this.managedPlayers.remove(entityplayer);
+        managedPlayersLock.writeLock().unlock(); // Akarin
+        this.e();
+    }
+
+    private boolean a(int i, int j, int k, int l, int i1) {
+        int j1 = i - k;
+        int k1 = j - l;
+
+        return j1 >= -i1 && j1 <= i1 ? k1 >= -i1 && k1 <= i1 : false;
+    }
+
+    public void movePlayer(EntityPlayer entityplayer) {
+        int i = (int) entityplayer.locX >> 4;
+        int j = (int) entityplayer.locZ >> 4;
+        double d0 = entityplayer.d - entityplayer.locX;
+        double d1 = entityplayer.e - entityplayer.locZ;
+        double d2 = d0 * d0 + d1 * d1;
+
+        if (d2 >= 64.0D) {
+            int k = (int) entityplayer.d >> 4;
+            int l = (int) entityplayer.e >> 4;
+            final int viewDistance = entityplayer.getViewDistance(); // Paper - Player view distance API
+            int i1 = Math.max(getViewDistance(), viewDistance); // Paper - Player view distance API
+
+            int j1 = i - k;
+            int k1 = j - l;
+
+            List<ChunkCoordIntPair> chunksToLoad = new LinkedList<ChunkCoordIntPair>(); // CraftBukkit
+
+            if (j1 != 0 || k1 != 0) {
+                for (int l1 = i - i1; l1 <= i + i1; ++l1) {
+                    for (int i2 = j - i1; i2 <= j + i1; ++i2) {
+                        if (!this.a(l1, i2, k, l, viewDistance)) { // Paper - Player view distance API
+                            // this.c(l1, i2).a(entityplayer);
+                            chunksToLoad.add(new ChunkCoordIntPair(l1, i2)); // CraftBukkit
+                        }
+
+                        if (!this.a(l1 - j1, i2 - k1, i, j, i1)) {
+                            PlayerChunk playerchunk = this.getChunk(l1 - j1, i2 - k1);
+
+                            if (playerchunk != null) {
+                                playerchunk.b(entityplayer);
+                            }
+                        }
+                    }
+                }
+
+                entityplayer.d = entityplayer.locX;
+                entityplayer.e = entityplayer.locZ;
+                this.e();
+
+                // CraftBukkit start - send nearest chunks first
+                Collections.sort(chunksToLoad, new ChunkCoordComparator(entityplayer));
+                synchronized (this) { // Akarin - synchronized
+                for (ChunkCoordIntPair pair : chunksToLoad) {
+                    this.c(pair.x, pair.z).a(entityplayer);
+                }
+                } // Akarin
+                // CraftBukkit end
+            }
+        }
+    }
+
+    public boolean a(EntityPlayer entityplayer, int i, int j) {
+        PlayerChunk playerchunk = this.getChunk(i, j);
+
+        return playerchunk != null && playerchunk.d(entityplayer) && playerchunk.e();
+    }
+
+    public final void setViewDistanceForAll(int viewDistance) { this.a(viewDistance); } // Paper - OBFHELPER
+    // Paper start - Separate into two methods
+    public void a(int i) {
+        i = MathHelper.clamp(i, 3, 32);
+        if (i != this.j) {
+            int j = i - this.j;
+            managedPlayersLock.readLock().lock(); // Akarin
+            ArrayList arraylist = Lists.newArrayList(this.managedPlayers);
+            managedPlayersLock.readLock().unlock(); // Akarin
+            Iterator iterator = arraylist.iterator();
+
+            while (iterator.hasNext()) {
+                EntityPlayer entityplayer = (EntityPlayer) iterator.next();
+                this.setViewDistance(entityplayer, i, false); // Paper - Split, don't mark sort pending, we'll handle it after
+            }
+
+            this.j = i;
+            this.e();
+        }
+    }
+
+    public void setViewDistance(EntityPlayer entityplayer, int i) {
+        this.setViewDistance(entityplayer, i, true); // Mark sort pending by default so we don't have to remember to do so all the time
+    }
+    
+    // Copied from above with minor changes
+    public void setViewDistance(EntityPlayer entityplayer, int i, boolean markSort) {
+        i = MathHelper.clamp(i, 3, 32);
+        int oldViewDistance = entityplayer.getViewDistance();
+        if (i != oldViewDistance) {
+            int j = i - oldViewDistance;
+            
+            int k = (int) entityplayer.locX >> 4;
+            int l = (int) entityplayer.locZ >> 4;
+            int i1;
+            int j1;
+
+            if (j > 0) {
+                synchronized (this) { // Akarin - synchronized
+                for (i1 = k - i; i1 <= k + i; ++i1) {
+                    for (j1 = l - i; j1 <= l + i; ++j1) {
+                        PlayerChunk playerchunk = this.c(i1, j1);
+
+                        if (!playerchunk.d(entityplayer)) {
+                            playerchunk.a(entityplayer);
+                        }
+                    }
+                }
+                } // Akarin
+            } else {
+                synchronized (this) { // Akarin - synchronized
+                for (i1 = k - oldViewDistance; i1 <= k + oldViewDistance; ++i1) {
+                    for (j1 = l - oldViewDistance; j1 <= l + oldViewDistance; ++j1) {
+                        if (!this.a(i1, j1, k, l, i)) {
+                            this.c(i1, j1).b(entityplayer);
+                        }
+                    }
+                }
+                } // Akarin
+                if (markSort) {
+                    this.e();
+                }
+            }
+        }
+    }
+    // Paper end
+
+    private void e() {
+        this.l = true;
+        this.m = true;
+    }
+
+    public static int getFurthestViewableBlock(int i) {
+        return i * 16 - 16;
+    }
+
+    private static long d(int i, int j) {
+        return (long) i + 2147483647L | (long) j + 2147483647L << 32;
+    }
+
+    public synchronized void a(PlayerChunk playerchunk) { // Akarin - synchronized
+        // org.spigotmc.AsyncCatcher.catchOp("Async Player Chunk Add"); // Paper // Akarin
+        this.f.add(playerchunk);
+    }
+
+    public synchronized void b(PlayerChunk playerchunk) { // Akarin - synchronized
+        org.spigotmc.AsyncCatcher.catchOp("Async Player Chunk Remove"); // Paper
+        ChunkCoordIntPair chunkcoordintpair = playerchunk.a();
+        long i = d(chunkcoordintpair.x, chunkcoordintpair.z);
+
+        playerchunk.c();
+        this.e.remove(i);
+        this.i.remove(playerchunk);
+        this.f.remove(playerchunk);
+        this.g.remove(playerchunk);
+        this.h.remove(playerchunk);
+        Chunk chunk = playerchunk.f();
+
+        if (chunk != null) {
+            // Paper start - delay chunk unloads
+            if (world.paperConfig.delayChunkUnloadsBy <= 0) {
+                this.getWorld().getChunkProviderServer().unload(chunk);
+            } else {
+                chunk.scheduledForUnload = System.currentTimeMillis();
+            }
+            // Paper end
+        }
+
+    }
+
+    // CraftBukkit start - Sorter to load nearby chunks first
+    private static class ChunkCoordComparator implements java.util.Comparator<ChunkCoordIntPair> {
+        private int x;
+        private int z;
+
+        public ChunkCoordComparator (EntityPlayer entityplayer) {
+            x = (int) entityplayer.locX >> 4;
+            z = (int) entityplayer.locZ >> 4;
+        }
+
+        public int compare(ChunkCoordIntPair a, ChunkCoordIntPair b) {
+            if (a.equals(b)) {
+                return 0;
+            }
+
+            // Subtract current position to set center point
+            int ax = a.x - this.x;
+            int az = a.z - this.z;
+            int bx = b.x - this.x;
+            int bz = b.z - this.z;
+
+            int result = ((ax - bx) * (ax + bx)) + ((az - bz) * (az + bz));
+            if (result != 0) {
+                return result;
+            }
+
+            if (ax < 0) {
+                if (bx < 0) {
+                    return bz - az;
+                } else {
+                    return -1;
+                }
+            } else {
+                if (bx < 0) {
+                    return 1;
+                } else {
+                    return az - bz;
+                }
+            }
+        }
+    }
+    // CraftBukkit end
+
+    // Paper start - Player view distance API
+    public void updateViewDistance(EntityPlayer player, int distanceIn) {
+        final int oldViewDistance = player.getViewDistance();
+
+        // This represents the view distance that we will set on the player
+        // It can exist as a negative value
+        int playerViewDistance = MathHelper.clamp(distanceIn, 3, 32);
+
+        // This value is the one we actually use to update the chunk map
+        // We don't ever want this to be a negative
+        int toSet = playerViewDistance;
+
+        if (distanceIn < 0) {
+            playerViewDistance = -1;
+            toSet = world.getPlayerChunkMap().getViewDistance();
+        }
+
+        if (toSet != oldViewDistance) {
+            // Order matters
+            this.setViewDistance(player, toSet);
+            player.setViewDistance(playerViewDistance);
+        }
+    }
+    // Paper end
+}

sources/src/main/java/net/minecraft/server/PlayerConnection.java

@@ -62,12 +62,11 @@ import co.aikar.timings.MinecraftTimings; // Paper
 // CraftBukkit end
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add volatile to fields<br>
- * 2) Expose private members<br>
- * 3) Migrated keep alive packet handling to service thread<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Add volatile to fields (slack service)
+ * 2) Expose private members (slack service)
+ * 3) Removed keep-alive codes (slack service)
+ * 4) Accessible keep-alive limit (feature, compatibility)
  */
 public class PlayerConnection implements PacketListenerPlayIn, ITickable {
 
@@ -76,12 +75,13 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
     private final MinecraftServer minecraftServer;
     public EntityPlayer player;
     private int e;
-    private volatile long f = getCurrentMillis(); public void setLastPing(long lastPing) { this.f = lastPing;}; public long getLastPing() { return this.f;}; // Paper - OBFHELPER - set ping to delay initial // Akarin - private -> public - volatile
-    private volatile boolean g; public void setPendingPing(boolean isPending) { this.g = isPending;}; public boolean isPendingPing() { return this.g;}; // Paper - OBFHELPER // Akarin - private -> public - volatile
-    private volatile long h; public void setKeepAliveID(long keepAliveID) { this.h = keepAliveID;}; public long getKeepAliveID() {return this.h; };  // Paper - OBFHELPER // Akarin - private -> public - volatile
+    private long f = getCurrentMillis(); public void setLastPing(long lastPing) { this.f = lastPing;}; public long getLastPing() { return this.f;}; // Paper - OBFHELPER - set ping to delay initial // Akarin - private -> public
+    private boolean g; public void setPendingPing(boolean isPending) { this.g = isPending;}; public boolean isPendingPing() { return this.g;}; // Paper - OBFHELPER // Akarin - private -> public
+    private long h; public void setKeepAliveID(long keepAliveID) { this.h = keepAliveID;}; public long getKeepAliveID() {return this.h; };  // Paper - OBFHELPER // Akarin - private -> public
     // CraftBukkit start - multithreaded fields
     private volatile int chatThrottle;
     private static final AtomicIntegerFieldUpdater chatSpamField = AtomicIntegerFieldUpdater.newUpdater(PlayerConnection.class, "chatThrottle");
+    private final java.util.concurrent.atomic.AtomicInteger tabSpamLimiter = new java.util.concurrent.atomic.AtomicInteger(); // Paper - configurable tab spam limits
     // CraftBukkit end
     private int j;
     private final IntHashMap<Short> k = new IntHashMap();
@@ -213,6 +213,7 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
         this.minecraftServer.methodProfiler.b();
         // CraftBukkit start
         for (int spam; (spam = this.chatThrottle) > 0 && !chatSpamField.compareAndSet(this, spam, spam - 1); ) ;
+        if (tabSpamLimiter.get() > 0) tabSpamLimiter.getAndDecrement(); // Paper - split to seperate variable
         /* Use thread-safe field access instead
         if (this.chatThrottle > 0) {
             --this.chatThrottle;
@@ -914,7 +915,8 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
             double d3 = d0 * d0 + d1 * d1 + d2 * d2;
 
             if (d3 > 36.0D) {
-                this.sendPacket(new PacketPlayOutBlockChange(worldserver, blockposition)); // Paper - Fix block break desync
+                if (worldserver.isChunkLoaded(blockposition.getX() >> 4, blockposition.getZ() >> 4, true)) // Paper - Fix block break desync - Don't send for unloaded chunks
+                    this.sendPacket(new PacketPlayOutBlockChange(worldserver, blockposition)); // Paper - Fix block break desync
                 return;
             } else if (blockposition.getY() >= this.minecraftServer.getMaxBuildHeight()) {
                 return;
@@ -1685,6 +1687,7 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
                     }
 
                     if (event.isCancelled()) {
+                        this.player.updateInventory(this.player.activeContainer); // Paper - Refresh player inventory
                         return;
                     }
                     // CraftBukkit end
@@ -2292,7 +2295,7 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
     // Paper start - async tab completion
     public void a(PacketPlayInTabComplete packet) {
         // CraftBukkit start
-        if (chatSpamField.addAndGet(this, 10) > 500 && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) {
+        if (tabSpamLimiter.addAndGet(com.destroystokyo.paper.PaperConfig.tabSpamIncrement) > com.destroystokyo.paper.PaperConfig.tabSpamLimit && !this.minecraftServer.getPlayerList().isOp(this.player.getProfile())) { // Paper start - split and make configurable
             minecraftServer.postToMainThread(() -> this.disconnect(new ChatMessage("disconnect.spam", new Object[0])));
             return;
         }

sources/src/main/java/net/minecraft/server/PlayerList.java

@@ -48,10 +48,8 @@ import org.spigotmc.event.player.PlayerSpawnLocationEvent;
 // CraftBukkit end
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Modify disconnect and connect messages<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Changes (dis)connect messages (feature)
  */
 public abstract class PlayerList {
 
@@ -1254,8 +1252,25 @@ public abstract class PlayerList {
     }
 
     public void sendPacketNearby(@Nullable EntityHuman entityhuman, double d0, double d1, double d2, double d3, int i, Packet<?> packet) {
-        for (int j = 0; j < this.players.size(); ++j) {
-            EntityPlayer entityplayer = this.players.get(j);
+     // Paper start - Use world list instead of server list where preferable
+        sendPacketNearby(entityhuman, d0, d1, d2, d3, i, null, packet); // Retained for compatibility
+    }
+
+    public void sendPacketNearby(@Nullable EntityHuman entityhuman, double d0, double d1, double d2, double d3, WorldServer world, Packet<?> packet) {
+        sendPacketNearby(entityhuman, d0, d1, d2, d3, world.dimension, world, packet);
+    }
+
+    public void sendPacketNearby(@Nullable EntityHuman entityhuman, double d0, double d1, double d2, double d3, int i, @Nullable WorldServer world, Packet<?> packet) {
+        if (world == null && entityhuman != null && entityhuman.world instanceof WorldServer) {
+            world = (WorldServer) entityhuman.world;
+        }
+
+        List<? extends EntityHuman> players1 = world == null ? players : world.players;
+        for (int j = 0; j < players1.size(); ++j) {
+            EntityHuman entity = players1.get(j);
+            if (!(entity instanceof EntityPlayer)) continue;
+            EntityPlayer entityplayer = (EntityPlayer) players1.get(j);
+            // Paper end
 
             // CraftBukkit start - Test if player receiving packet can see the source of the packet
             if (entityhuman != null && entityhuman instanceof EntityPlayer && !entityplayer.getBukkitEntity().canSee(((EntityPlayer) entityhuman).getBukkitEntity())) {
@@ -1263,7 +1278,7 @@ public abstract class PlayerList {
             }
             // CraftBukkit end
 
-            if (entityplayer != entityhuman && entityplayer.dimension == i) {
+            if (entityplayer != entityhuman && (world != null || entityplayer.dimension == i)) { // Paper
                 double d4 = d0 - entityplayer.locX;
                 double d5 = d1 - entityplayer.locY;
                 double d6 = d2 - entityplayer.locZ;

sources/src/main/java/net/minecraft/server/RegionFileCache.java

@@ -0,0 +1,127 @@
+package net.minecraft.server;
+
+import com.destroystokyo.paper.exception.ServerInternalException;
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.Map;
+import com.destroystokyo.paper.PaperConfig; // Paper
+import java.util.LinkedHashMap; // Paper
+
+/**
+ * Akarin Changes Note
+ * 1) Removes unneed synchronization (performance)
+ */
+public class RegionFileCache {
+
+    public static final Map<File, RegionFile> a = new LinkedHashMap(PaperConfig.regionFileCacheSize, 0.75f, true); // Spigot - private -> public, Paper - HashMap -> LinkedHashMap
+
+    public static synchronized RegionFile a(File file, int i, int j) {
+        File file1 = new File(file, "region");
+        File file2 = new File(file1, "r." + (i >> 5) + "." + (j >> 5) + ".mca");
+        RegionFile regionfile = (RegionFile) RegionFileCache.a.get(file2);
+
+        if (regionfile != null) {
+            return regionfile;
+        } else {
+            if (!file1.exists()) {
+                file1.mkdirs();
+            }
+
+            if (RegionFileCache.a.size() >= PaperConfig.regionFileCacheSize) { // Paper
+                trimCache(); // Paper
+            }
+
+            RegionFile regionfile1 = new RegionFile(file2);
+
+            RegionFileCache.a.put(file2, regionfile1);
+            return regionfile1;
+        }
+    }
+
+    public static synchronized RegionFile b(File file, int i, int j) {
+        File file1 = new File(file, "region");
+        File file2 = new File(file1, "r." + (i >> 5) + "." + (j >> 5) + ".mca");
+        RegionFile regionfile = (RegionFile) RegionFileCache.a.get(file2);
+
+        if (regionfile != null) {
+            return regionfile;
+        } else if (file1.exists() && file2.exists()) {
+            if (RegionFileCache.a.size() >= 256) {
+                a();
+            }
+
+            RegionFile regionfile1 = new RegionFile(file2);
+
+            RegionFileCache.a.put(file2, regionfile1);
+            return regionfile1;
+        } else {
+            return null;
+        }
+    }
+
+    // Paper Start
+    private static synchronized void trimCache() {
+        Iterator<Map.Entry<File, RegionFile>> itr = RegionFileCache.a.entrySet().iterator();
+        int count = RegionFileCache.a.size() - PaperConfig.regionFileCacheSize;
+        while (count-- >= 0 && itr.hasNext()) {
+            try {
+                itr.next().getValue().c();
+            } catch (IOException ioexception) {
+                ioexception.printStackTrace();
+                ServerInternalException.reportInternalException(ioexception);
+            }
+            itr.remove();
+        }
+    }
+    // Paper End
+
+    public static synchronized void a() {
+        Iterator iterator = RegionFileCache.a.values().iterator();
+
+        while (iterator.hasNext()) {
+            RegionFile regionfile = (RegionFile) iterator.next();
+
+            try {
+                if (regionfile != null) {
+                    regionfile.c();
+                }
+            } catch (IOException ioexception) {
+                ioexception.printStackTrace();
+                ServerInternalException.reportInternalException(ioexception); // Paper
+            }
+        }
+
+        RegionFileCache.a.clear();
+    }
+
+    // CraftBukkit start - call sites hoisted for synchronization
+    public static /*synchronized*/ NBTTagCompound d(File file, int i, int j) throws IOException { // Akarin - 1.13 backport - remove synchronization // OBFHELPER: read
+        RegionFile regionfile = a(file, i, j);
+
+        DataInputStream datainputstream = regionfile.a(i & 31, j & 31);
+
+        if (datainputstream == null) {
+            return null;
+        }
+
+        return NBTCompressedStreamTools.a(datainputstream);
+    }
+
+    public static /*synchronized*/ void e(File file, int i, int j, NBTTagCompound nbttagcompound) throws IOException { // Akarin - 1.13 backport - remove synchronization // OBFHELPER: write
+        RegionFile regionfile = a(file, i, j);
+
+        DataOutputStream dataoutputstream = regionfile.b(i & 31, j & 31);
+        NBTCompressedStreamTools.a(nbttagcompound, (java.io.DataOutput) dataoutputstream);
+        dataoutputstream.close();
+    }
+    // CraftBukkit end
+
+    public static /*synchronized*/ boolean chunkExists(File file, int i, int j) { // Akarin - 1.13 backport - remove synchronization
+        RegionFile regionfile = b(file, i, j);
+
+        return regionfile != null ? regionfile.c(i & 31, j & 31) : false;
+    }
+}

sources/src/main/java/net/minecraft/server/RegistryID.java

@@ -0,0 +1,163 @@
+package net.minecraft.server;
+
+import com.google.common.base.Predicates;
+import com.google.common.collect.Iterators;
+
+import java.util.BitSet;
+import java.util.Iterator;
+import javax.annotation.Nullable;
+
+/**
+ * Akarin Changes Note
+ * 1) BitSet for faster access (performance)
+ */
+public class RegistryID<K> implements Registry {
+
+    private static final Object a = null;
+    private K[] b;
+    private int[] c;
+    private K[] d;
+    private int e;
+    private int f;
+    private java.util.BitSet usedIds; // Akarin - 1.13 backport
+
+    public RegistryID(int i) {
+        i = (int) ((float) i / 0.8F);
+        this.b = (K[]) (new Object[i]);
+        this.c = new int[i];
+        this.d = (K[]) (new Object[i]);
+        this.usedIds = new BitSet(); // Akarin - 1.13 backport
+    }
+
+    public int getId(@Nullable K k0) {
+        return this.c(this.b(k0, this.d(k0)));
+    }
+
+    @Nullable
+    public K fromId(int i) {
+        return i >= 0 && i < this.d.length ? this.d[i] : null;
+    }
+
+    private int c(int i) {
+        return i == -1 ? -1 : this.c[i];
+    }
+
+    public int c(K k0) {
+        int i = this.c();
+
+        this.a(k0, i);
+        return i;
+    }
+
+    private int c() {
+        // Akarin start - 1.13 backport
+        /*
+        while (this.e < this.d.length && this.d[this.e] != null) {
+            ++this.e;
+        }
+        */
+        this.e = this.usedIds.nextClearBit(0);
+        // Akarin end - 1.13 backport
+
+        return this.e;
+    }
+
+    private void d(int i) {
+        K[] aobject = this.b;
+        int[] aint = this.c;
+
+        this.b = (K[]) (new Object[i]);
+        this.c = new int[i];
+        this.d = (K[]) (new Object[i]);
+        this.e = 0;
+        this.f = 0;
+        this.usedIds.clear(); // Akarin - 1.13 backport
+
+        for (int j = 0; j < aobject.length; ++j) {
+            if (aobject[j] != null) {
+                this.a(aobject[j], aint[j]);
+            }
+        }
+
+    }
+
+    public void a(K k0, int i) {
+        int j = Math.max(i, this.f + 1);
+        int k;
+
+        if ((float) j >= (float) this.b.length * 0.8F) {
+            for (k = this.b.length << 1; k < i; k <<= 1) {
+                ;
+            }
+
+            this.d(k);
+        }
+
+        k = this.e(this.d(k0));
+        this.b[k] = k0;
+        this.c[k] = i;
+        this.d[i] = k0;
+        this.usedIds.set(i); // Akarin - 1.13 backport
+        ++this.f;
+        if (i == this.e) {
+            ++this.e;
+        }
+
+    }
+
+    private int d(@Nullable K k0) {
+        return (MathHelper.f(System.identityHashCode(k0)) & Integer.MAX_VALUE) % this.b.length;
+    }
+
+    private int b(@Nullable K k0, int i) {
+        int j;
+
+        for (j = i; j < this.b.length; ++j) {
+            if (this.b[j] == k0) {
+                return j;
+            }
+
+            if (this.b[j] == RegistryID.a) {
+                return -1;
+            }
+        }
+
+        for (j = 0; j < i; ++j) {
+            if (this.b[j] == k0) {
+                return j;
+            }
+
+            if (this.b[j] == RegistryID.a) {
+                return -1;
+            }
+        }
+
+        return -1;
+    }
+
+    private int e(int i) {
+        int j;
+
+        for (j = i; j < this.b.length; ++j) {
+            if (this.b[j] == RegistryID.a) {
+                return j;
+            }
+        }
+
+        for (j = 0; j < i; ++j) {
+            if (this.b[j] == RegistryID.a) {
+                return j;
+            }
+        }
+
+        throw new RuntimeException("Overflowed :(");
+    }
+
+    public Iterator<K> iterator() {
+        return Iterators.filter(Iterators.forArray(this.d), Predicates.notNull());
+    }
+
+    public int b() {
+        return this.f;
+    }
+}

sources/src/main/java/net/minecraft/server/TileEntitySkull.java

@@ -0,0 +1,265 @@
+package net.minecraft.server;
+
+import com.google.common.collect.Iterables;
+import com.mojang.authlib.GameProfile;
+import com.mojang.authlib.minecraft.MinecraftSessionService;
+import com.mojang.authlib.properties.Property;
+import java.util.UUID;
+import javax.annotation.Nullable;
+
+// Spigot start
+import com.google.common.base.Predicate;
+import com.google.common.cache.LoadingCache;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.CacheLoader;
+import com.google.common.util.concurrent.Futures;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+
+import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.mojang.authlib.Agent;
+import com.mojang.authlib.ProfileLookupCallback;
+import java.util.concurrent.Callable;
+// Spigot end
+
+/**
+ * Akarin Changes Note
+ * 1) Guava -> Caffeine (performance)
+ */
+public class TileEntitySkull extends TileEntity /*implements ITickable*/ { // Paper - remove tickable
+
+    private int a;
+    public int rotation;
+    private GameProfile g;
+    private int h;
+    private boolean i;
+    private static UserCache j;
+    private static MinecraftSessionService k;
+    // Spigot start
+    public static final ExecutorService executor = Executors.newFixedThreadPool(3,
+            new ThreadFactoryBuilder()
+                    .setNameFormat("Head Conversion Thread - %1$d")
+                    .build()
+    );
+    public static final com.github.benmanes.caffeine.cache.LoadingCache<String, GameProfile> skinCache = com.github.benmanes.caffeine.cache.Caffeine.newBuilder() // Akarin - caffeine
+            .maximumSize( 5000 )
+            .expireAfterAccess( 60, TimeUnit.MINUTES )
+            .build( new com.github.benmanes.caffeine.cache.CacheLoader<String, GameProfile>() // Akarin - caffeine
+            {
+                @Override
+                public GameProfile load(String key) // Akarin - remove exception
+                {
+                    final GameProfile[] profiles = new GameProfile[1];
+                    ProfileLookupCallback gameProfileLookup = new ProfileLookupCallback() {
+
+                        @Override
+                        public void onProfileLookupSucceeded(GameProfile gp) {
+                            profiles[0] = gp;
+                        }
+
+                        @Override
+                        public void onProfileLookupFailed(GameProfile gp, Exception excptn) {
+                            profiles[0] = gp;
+                        }
+                    };
+
+                    MinecraftServer.getServer().getGameProfileRepository().findProfilesByNames(new String[] { key }, Agent.MINECRAFT, gameProfileLookup);
+
+                    GameProfile profile = profiles[ 0 ];
+                    if (profile == null) {
+                        UUID uuid = EntityHuman.a(new GameProfile(null, key));
+                        profile = new GameProfile(uuid, key);
+
+                        gameProfileLookup.onProfileLookupSucceeded(profile);
+                    } else
+                    {
+
+                        Property property = Iterables.getFirst( profile.getProperties().get( "textures" ), null );
+
+                        if ( property == null )
+                        {
+                            profile = MinecraftServer.getServer().az().fillProfileProperties( profile, true );
+                        }
+                    }
+
+
+                    return profile;
+                }
+            } );
+    // Spigot end
+
+    public TileEntitySkull() {}
+
+    public static void a(UserCache usercache) {
+        TileEntitySkull.j = usercache;
+    }
+
+    public static void a(MinecraftSessionService minecraftsessionservice) {
+        TileEntitySkull.k = minecraftsessionservice;
+    }
+
+    public NBTTagCompound save(NBTTagCompound nbttagcompound) {
+        super.save(nbttagcompound);
+        nbttagcompound.setByte("SkullType", (byte) (this.a & 255));
+        nbttagcompound.setByte("Rot", (byte) (this.rotation & 255));
+        if (this.g != null) {
+            NBTTagCompound nbttagcompound1 = new NBTTagCompound();
+
+            GameProfileSerializer.serialize(nbttagcompound1, this.g);
+            nbttagcompound.set("Owner", nbttagcompound1);
+        }
+
+        return nbttagcompound;
+    }
+
+    public void load(NBTTagCompound nbttagcompound) {
+        super.load(nbttagcompound);
+        this.a = nbttagcompound.getByte("SkullType");
+        this.rotation = nbttagcompound.getByte("Rot");
+        if (this.a == 3) {
+            if (nbttagcompound.hasKeyOfType("Owner", 10)) {
+                this.g = GameProfileSerializer.deserialize(nbttagcompound.getCompound("Owner"));
+            } else if (nbttagcompound.hasKeyOfType("ExtraType", 8)) {
+                String s = nbttagcompound.getString("ExtraType");
+
+                if (!UtilColor.b(s)) {
+                    this.g = new GameProfile((UUID) null, s);
+                    this.i();
+                }
+            }
+        }
+
+    }
+
+    public void e() {
+        if (this.a == 5) {
+            if (this.world.isBlockIndirectlyPowered(this.position)) {
+                this.i = true;
+                ++this.h;
+            } else {
+                this.i = false;
+            }
+        }
+
+    }
+
+    @Nullable
+    public GameProfile getGameProfile() {
+        return this.g;
+    }
+
+    @Nullable
+    public PacketPlayOutTileEntityData getUpdatePacket() {
+        return new PacketPlayOutTileEntityData(this.position, 4, this.d());
+    }
+
+    public NBTTagCompound d() {
+        return this.save(new NBTTagCompound());
+    }
+
+    public void setSkullType(int i) {
+        this.a = i;
+        this.g = null;
+    }
+
+    public void setGameProfile(@Nullable GameProfile gameprofile) {
+        this.a = 3;
+        this.g = gameprofile;
+        this.i();
+    }
+
+    private void i() {
+        // Spigot start
+        GameProfile profile = this.g;
+        setSkullType( 0 ); // Work around client bug
+        b(profile, new Predicate<GameProfile>() {
+
+            @Override
+            public boolean apply(GameProfile input) {
+                setSkullType(3); // Work around client bug
+                g = input;
+                update();
+                if (world != null) {
+                    world.m(position); // PAIL: notify
+                }
+                return false;
+            }
+        }, false); 
+        // Spigot end
+    }
+
+    // Spigot start - Support async lookups
+    public static Future<GameProfile> b(final GameProfile gameprofile, final Predicate<GameProfile> callback, boolean sync) {
+        if (gameprofile != null && !UtilColor.b(gameprofile.getName())) {
+            if (gameprofile.isComplete() && gameprofile.getProperties().containsKey("textures")) {
+                callback.apply(gameprofile);
+            } else if (MinecraftServer.getServer() == null) {
+                callback.apply(gameprofile);
+            } else {
+                GameProfile profile = skinCache.getIfPresent(gameprofile.getName().toLowerCase(java.util.Locale.ROOT));
+                if (profile != null && Iterables.getFirst(profile.getProperties().get("textures"), (Object) null) != null) {
+                    callback.apply(profile);
+
+                    return Futures.immediateFuture(profile);
+                } else {
+                    Callable<GameProfile> callable = new Callable<GameProfile>() {
+                        @Override
+                        public GameProfile call() {
+                            final GameProfile profile = skinCache.get(gameprofile.getName().toLowerCase(java.util.Locale.ROOT)); // Akarin - caffeine
+                            MinecraftServer.getServer().processQueue.add(new Runnable() {
+                                @Override
+                                public void run() {
+                                    if (profile == null) {
+                                        callback.apply(gameprofile);
+                                    } else {
+                                        callback.apply(profile);
+                                    }
+                                }
+                            });
+                            return profile;
+                        }
+                    };
+                    if (sync) {
+                        try {
+                            return Futures.immediateFuture(callable.call());
+                        } catch (Exception ex) {
+                            com.google.common.base.Throwables.throwIfUnchecked(ex);
+                            throw new RuntimeException(ex); // Not possible
+                        }
+                    } else {
+                        return executor.submit(callable);
+                    }
+                }
+            }
+        } else {
+            callback.apply(gameprofile);
+        }
+
+        return Futures.immediateFuture(gameprofile);
+    }
+    // Spigot end
+
+    public int getSkullType() {
+        return this.a;
+    }
+
+    public void setRotation(int i) {
+        this.rotation = i;
+    }
+
+    public void a(EnumBlockMirror enumblockmirror) {
+        if (this.world != null && this.world.getType(this.getPosition()).get(BlockSkull.FACING) == EnumDirection.UP) {
+            this.rotation = enumblockmirror.a(this.rotation, 16);
+        }
+
+    }
+
+    public void a(EnumBlockRotation enumblockrotation) {
+        if (this.world != null && this.world.getType(this.getPosition()).get(BlockSkull.FACING) == EnumDirection.UP) {
+            this.rotation = enumblockrotation.a(this.rotation, 16);
+        }
+
+    }
+}

sources/src/main/java/net/minecraft/server/WorldData.java

@@ -1,775 +0,0 @@
-package net.minecraft.server;
-
-import com.google.common.collect.Maps;
-import java.util.Iterator;
-import java.util.Map;
-import java.util.Map.Entry;
-import javax.annotation.Nullable;
-// CraftBukkit start
-import org.bukkit.Bukkit;
-import org.bukkit.event.weather.ThunderChangeEvent;
-import org.bukkit.event.weather.WeatherChangeEvent;
-// CraftBukkit end
-
-/**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Add volatile to fields<br>
- * @author cakoyo
- */
-public class WorldData {
-
-    private String b;
-    private int c;
-    private boolean d;
-    public static final EnumDifficulty a = EnumDifficulty.NORMAL;
-    private long e;
-    private WorldType f;
-    private String g;
-    private int h;
-    private int i;
-    private int j;
-    private volatile long k; // Akarin - volatile - PAIL: time
-    private volatile long l; // Akarin - volatile - PAIL: dayTime
-    private long m;
-    private long n;
-    private NBTTagCompound o;
-    private int p;
-    private String levelName;
-    private int r;
-    private int s;
-    private boolean t;
-    private int u;
-    private boolean v;
-    private int w;
-    private EnumGamemode x;
-    private boolean y;
-    private boolean z;
-    private boolean A;
-    private boolean B;
-    private volatile EnumDifficulty C; // Akarin - volatile
-    private boolean D;
-    private double E;
-    private double F;
-    private double G;
-    private long H;
-    private double I;
-    private double J;
-    private double K;
-    private int L;
-    private int M;
-    private final Map<DimensionManager, NBTTagCompound> N;
-    private GameRules O;
-    public WorldServer world; // CraftBukkit
-
-    protected WorldData() {
-        this.f = WorldType.NORMAL;
-        this.g = "";
-        this.G = 6.0E7D;
-        this.J = 5.0D;
-        this.K = 0.2D;
-        this.L = 5;
-        this.M = 15;
-        this.N = Maps.newEnumMap(DimensionManager.class);
-        this.O = new GameRules();
-    }
-
-    public static void a(DataConverterManager dataconvertermanager) {
-        dataconvertermanager.a(DataConverterTypes.LEVEL, new DataInspector() {
-            @Override
-            public NBTTagCompound a(DataConverter dataconverter, NBTTagCompound nbttagcompound, int i) {
-                if (nbttagcompound.hasKeyOfType("Player", 10)) {
-                    nbttagcompound.set("Player", dataconverter.a(DataConverterTypes.PLAYER, nbttagcompound.getCompound("Player"), i));
-                }
-
-                return nbttagcompound;
-            }
-        });
-    }
-
-    public WorldData(NBTTagCompound nbttagcompound) {
-        this.f = WorldType.NORMAL;
-        this.g = "";
-        this.G = 6.0E7D;
-        this.J = 5.0D;
-        this.K = 0.2D;
-        this.L = 5;
-        this.M = 15;
-        this.N = Maps.newEnumMap(DimensionManager.class);
-        this.O = new GameRules();
-        NBTTagCompound nbttagcompound1;
-
-        if (nbttagcompound.hasKeyOfType("Version", 10)) {
-            nbttagcompound1 = nbttagcompound.getCompound("Version");
-            this.b = nbttagcompound1.getString("Name");
-            this.c = nbttagcompound1.getInt("Id");
-            this.d = nbttagcompound1.getBoolean("Snapshot");
-        }
-
-        this.e = nbttagcompound.getLong("RandomSeed");
-        if (nbttagcompound.hasKeyOfType("generatorName", 8)) {
-            String s = nbttagcompound.getString("generatorName");
-
-            this.f = WorldType.getType(s);
-            if (this.f == null) {
-                this.f = WorldType.NORMAL;
-            } else if (this.f.f()) {
-                int i = 0;
-
-                if (nbttagcompound.hasKeyOfType("generatorVersion", 99)) {
-                    i = nbttagcompound.getInt("generatorVersion");
-                }
-
-                this.f = this.f.a(i);
-            }
-
-            if (nbttagcompound.hasKeyOfType("generatorOptions", 8)) {
-                this.g = nbttagcompound.getString("generatorOptions");
-            }
-        }
-
-        this.x = EnumGamemode.getById(nbttagcompound.getInt("GameType"));
-        if (nbttagcompound.hasKeyOfType("MapFeatures", 99)) {
-            this.y = nbttagcompound.getBoolean("MapFeatures");
-        } else {
-            this.y = true;
-        }
-
-        this.h = nbttagcompound.getInt("SpawnX");
-        this.i = nbttagcompound.getInt("SpawnY");
-        this.j = nbttagcompound.getInt("SpawnZ");
-        this.k = nbttagcompound.getLong("Time");
-        if (nbttagcompound.hasKeyOfType("DayTime", 99)) {
-            this.l = nbttagcompound.getLong("DayTime");
-        } else {
-            this.l = this.k;
-        }
-
-        this.m = nbttagcompound.getLong("LastPlayed");
-        this.n = nbttagcompound.getLong("SizeOnDisk");
-        this.levelName = nbttagcompound.getString("LevelName");
-        this.r = nbttagcompound.getInt("version");
-        this.s = nbttagcompound.getInt("clearWeatherTime");
-        this.u = nbttagcompound.getInt("rainTime");
-        this.t = nbttagcompound.getBoolean("raining");
-        this.w = nbttagcompound.getInt("thunderTime");
-        this.v = nbttagcompound.getBoolean("thundering");
-        this.z = nbttagcompound.getBoolean("hardcore");
-        if (nbttagcompound.hasKeyOfType("initialized", 99)) {
-            this.B = nbttagcompound.getBoolean("initialized");
-        } else {
-            this.B = true;
-        }
-
-        if (nbttagcompound.hasKeyOfType("allowCommands", 99)) {
-            this.A = nbttagcompound.getBoolean("allowCommands");
-        } else {
-            this.A = this.x == EnumGamemode.CREATIVE;
-        }
-
-        if (nbttagcompound.hasKeyOfType("Player", 10)) {
-            this.o = nbttagcompound.getCompound("Player");
-            this.p = this.o.getInt("Dimension");
-        }
-
-        if (nbttagcompound.hasKeyOfType("GameRules", 10)) {
-            this.O.a(nbttagcompound.getCompound("GameRules"));
-        }
-
-        if (nbttagcompound.hasKeyOfType("Difficulty", 99)) {
-            this.C = EnumDifficulty.getById(nbttagcompound.getByte("Difficulty"));
-        }
-
-        if (nbttagcompound.hasKeyOfType("DifficultyLocked", 1)) {
-            this.D = nbttagcompound.getBoolean("DifficultyLocked");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderCenterX", 99)) {
-            this.E = nbttagcompound.getDouble("BorderCenterX");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderCenterZ", 99)) {
-            this.F = nbttagcompound.getDouble("BorderCenterZ");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderSize", 99)) {
-            this.G = nbttagcompound.getDouble("BorderSize");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderSizeLerpTime", 99)) {
-            this.H = nbttagcompound.getLong("BorderSizeLerpTime");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderSizeLerpTarget", 99)) {
-            this.I = nbttagcompound.getDouble("BorderSizeLerpTarget");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderSafeZone", 99)) {
-            this.J = nbttagcompound.getDouble("BorderSafeZone");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderDamagePerBlock", 99)) {
-            this.K = nbttagcompound.getDouble("BorderDamagePerBlock");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderWarningBlocks", 99)) {
-            this.L = nbttagcompound.getInt("BorderWarningBlocks");
-        }
-
-        if (nbttagcompound.hasKeyOfType("BorderWarningTime", 99)) {
-            this.M = nbttagcompound.getInt("BorderWarningTime");
-        }
-
-        if (nbttagcompound.hasKeyOfType("DimensionData", 10)) {
-            nbttagcompound1 = nbttagcompound.getCompound("DimensionData");
-            Iterator iterator = nbttagcompound1.c().iterator();
-
-            while (iterator.hasNext()) {
-                String s1 = (String) iterator.next();
-
-                this.N.put(DimensionManager.a(Integer.parseInt(s1)), nbttagcompound1.getCompound(s1));
-            }
-        }
-
-    }
-
-    public WorldData(WorldSettings worldsettings, String s) {
-        this.f = WorldType.NORMAL;
-        this.g = "";
-        this.G = 6.0E7D;
-        this.J = 5.0D;
-        this.K = 0.2D;
-        this.L = 5;
-        this.M = 15;
-        this.N = Maps.newEnumMap(DimensionManager.class);
-        this.O = new GameRules();
-        this.a(worldsettings);
-        this.levelName = s;
-        this.C = WorldData.a;
-        this.B = false;
-    }
-
-    public void a(WorldSettings worldsettings) {
-        this.e = worldsettings.d();
-        this.x = worldsettings.e();
-        this.y = worldsettings.g();
-        this.z = worldsettings.f();
-        this.f = worldsettings.h();
-        this.g = worldsettings.j();
-        this.A = worldsettings.i();
-    }
-
-    public WorldData(WorldData worlddata) {
-        this.f = WorldType.NORMAL;
-        this.g = "";
-        this.G = 6.0E7D;
-        this.J = 5.0D;
-        this.K = 0.2D;
-        this.L = 5;
-        this.M = 15;
-        this.N = Maps.newEnumMap(DimensionManager.class);
-        this.O = new GameRules();
-        this.e = worlddata.e;
-        this.f = worlddata.f;
-        this.g = worlddata.g;
-        this.x = worlddata.x;
-        this.y = worlddata.y;
-        this.h = worlddata.h;
-        this.i = worlddata.i;
-        this.j = worlddata.j;
-        this.k = worlddata.k;
-        this.l = worlddata.l;
-        this.m = worlddata.m;
-        this.n = worlddata.n;
-        this.o = worlddata.o;
-        this.p = worlddata.p;
-        this.levelName = worlddata.levelName;
-        this.r = worlddata.r;
-        this.u = worlddata.u;
-        this.t = worlddata.t;
-        this.w = worlddata.w;
-        this.v = worlddata.v;
-        this.z = worlddata.z;
-        this.A = worlddata.A;
-        this.B = worlddata.B;
-        this.O = worlddata.O;
-        this.C = worlddata.C;
-        this.D = worlddata.D;
-        this.E = worlddata.E;
-        this.F = worlddata.F;
-        this.G = worlddata.G;
-        this.H = worlddata.H;
-        this.I = worlddata.I;
-        this.J = worlddata.J;
-        this.K = worlddata.K;
-        this.M = worlddata.M;
-        this.L = worlddata.L;
-    }
-
-    public NBTTagCompound a(@Nullable NBTTagCompound nbttagcompound) {
-        if (nbttagcompound == null) {
-            nbttagcompound = this.o;
-        }
-
-        NBTTagCompound nbttagcompound1 = new NBTTagCompound();
-
-        this.a(nbttagcompound1, nbttagcompound);
-        return nbttagcompound1;
-    }
-
-    private void a(NBTTagCompound nbttagcompound, NBTTagCompound nbttagcompound1) {
-        NBTTagCompound nbttagcompound2 = new NBTTagCompound();
-
-        nbttagcompound2.setString("Name", "1.12.2");
-        nbttagcompound2.setInt("Id", 1343);
-        nbttagcompound2.setBoolean("Snapshot", false);
-        nbttagcompound.set("Version", nbttagcompound2);
-        nbttagcompound.setInt("DataVersion", 1343);
-        nbttagcompound.setLong("RandomSeed", this.e);
-        nbttagcompound.setString("generatorName", this.f.name());
-        nbttagcompound.setInt("generatorVersion", this.f.getVersion());
-        nbttagcompound.setString("generatorOptions", this.g);
-        nbttagcompound.setInt("GameType", this.x.getId());
-        nbttagcompound.setBoolean("MapFeatures", this.y);
-        nbttagcompound.setInt("SpawnX", this.h);
-        nbttagcompound.setInt("SpawnY", this.i);
-        nbttagcompound.setInt("SpawnZ", this.j);
-        nbttagcompound.setLong("Time", this.k);
-        nbttagcompound.setLong("DayTime", this.l);
-        nbttagcompound.setLong("SizeOnDisk", this.n);
-        nbttagcompound.setLong("LastPlayed", MinecraftServer.aw());
-        nbttagcompound.setString("LevelName", this.levelName);
-        nbttagcompound.setInt("version", this.r);
-        nbttagcompound.setInt("clearWeatherTime", this.s);
-        nbttagcompound.setInt("rainTime", this.u);
-        nbttagcompound.setBoolean("raining", this.t);
-        nbttagcompound.setInt("thunderTime", this.w);
-        nbttagcompound.setBoolean("thundering", this.v);
-        nbttagcompound.setBoolean("hardcore", this.z);
-        nbttagcompound.setBoolean("allowCommands", this.A);
-        nbttagcompound.setBoolean("initialized", this.B);
-        nbttagcompound.setDouble("BorderCenterX", this.E);
-        nbttagcompound.setDouble("BorderCenterZ", this.F);
-        nbttagcompound.setDouble("BorderSize", this.G);
-        nbttagcompound.setLong("BorderSizeLerpTime", this.H);
-        nbttagcompound.setDouble("BorderSafeZone", this.J);
-        nbttagcompound.setDouble("BorderDamagePerBlock", this.K);
-        nbttagcompound.setDouble("BorderSizeLerpTarget", this.I);
-        nbttagcompound.setDouble("BorderWarningBlocks", this.L);
-        nbttagcompound.setDouble("BorderWarningTime", this.M);
-        if (this.C != null) {
-            nbttagcompound.setByte("Difficulty", (byte) this.C.a());
-        }
-
-        nbttagcompound.setBoolean("DifficultyLocked", this.D);
-        nbttagcompound.set("GameRules", this.O.a());
-        NBTTagCompound nbttagcompound3 = new NBTTagCompound();
-        Iterator iterator = this.N.entrySet().iterator();
-
-        while (iterator.hasNext()) {
-            Entry entry = (Entry) iterator.next();
-
-            nbttagcompound3.set(String.valueOf(((DimensionManager) entry.getKey()).getDimensionID()), (NBTBase) entry.getValue());
-        }
-
-        nbttagcompound.set("DimensionData", nbttagcompound3);
-        if (nbttagcompound1 != null) {
-            nbttagcompound.set("Player", nbttagcompound1);
-        }
-
-    }
-
-    public long getSeed() {
-        return this.e;
-    }
-
-    public int b() {
-        return this.h;
-    }
-
-    public int c() {
-        return this.i;
-    }
-
-    public int d() {
-        return this.j;
-    }
-
-    public long getTime() {
-        return this.k;
-    }
-
-    public long getDayTime() {
-        return this.l;
-    }
-
-    public NBTTagCompound h() {
-        return this.o;
-    }
-
-    public void setTime(long i) {
-        this.k = i;
-    }
-
-    public void setDayTime(long i) {
-        this.l = i;
-    }
-
-    public void setSpawn(BlockPosition blockposition) {
-        this.h = blockposition.getX();
-        this.i = blockposition.getY();
-        this.j = blockposition.getZ();
-    }
-
-    public String getName() {
-        return this.levelName;
-    }
-
-    public void a(String s) {
-        this.levelName = s;
-    }
-
-    public int k() {
-        return this.r;
-    }
-
-    public void e(int i) {
-        this.r = i;
-    }
-
-    public int z() {
-        return this.s;
-    }
-
-    public void i(int i) {
-        this.s = i;
-    }
-
-    public boolean isThundering() {
-        return this.v;
-    }
-
-    public void setThundering(boolean flag) {
-        // CraftBukkit start
-        org.bukkit.World world = Bukkit.getWorld(getName());
-        if (world != null) {
-            ThunderChangeEvent thunder = new ThunderChangeEvent(world, flag);
-            Bukkit.getServer().getPluginManager().callEvent(thunder);
-            if (thunder.isCancelled()) {
-                return;
-            }
-        }
-        // CraftBukkit end
-        this.v = flag;
-    }
-
-    public int getThunderDuration() {
-        return this.w;
-    }
-
-    public void setThunderDuration(int i) {
-        this.w = i;
-    }
-
-    public boolean hasStorm() {
-        return this.t;
-    }
-
-    public void setStorm(boolean flag) {
-        // CraftBukkit start
-        org.bukkit.World world = Bukkit.getWorld(getName());
-        if (world != null) {
-            WeatherChangeEvent weather = new WeatherChangeEvent(world, flag);
-            Bukkit.getServer().getPluginManager().callEvent(weather);
-            if (weather.isCancelled()) {
-                return;
-            }
-        }
-        // CraftBukkit end
-        this.t = flag;
-    }
-
-    public int getWeatherDuration() {
-        return this.u;
-    }
-
-    public void setWeatherDuration(int i) {
-        this.u = i;
-    }
-
-    public EnumGamemode getGameType() {
-        return this.x;
-    }
-
-    public boolean shouldGenerateMapFeatures() {
-        return this.y;
-    }
-
-    public void f(boolean flag) {
-        this.y = flag;
-    }
-
-    public void setGameType(EnumGamemode enumgamemode) {
-        this.x = enumgamemode;
-    }
-
-    public boolean isHardcore() {
-        return this.z;
-    }
-
-    public void g(boolean flag) {
-        this.z = flag;
-    }
-
-    public WorldType getType() {
-        return this.f;
-    }
-
-    public void a(WorldType worldtype) {
-        this.f = worldtype;
-    }
-
-    public String getGeneratorOptions() {
-        return this.g == null ? "" : this.g;
-    }
-
-    public boolean u() {
-        return this.A;
-    }
-
-    public void c(boolean flag) {
-        this.A = flag;
-    }
-
-    public boolean v() {
-        return this.B;
-    }
-
-    public void d(boolean flag) {
-        this.B = flag;
-    }
-
-    public GameRules w() {
-        return this.O;
-    }
-
-    public double B() {
-        return this.E;
-    }
-
-    public double C() {
-        return this.F;
-    }
-
-    public double D() {
-        return this.G;
-    }
-
-    public void a(double d0) {
-        this.G = d0;
-    }
-
-    public long E() {
-        return this.H;
-    }
-
-    public void e(long i) {
-        this.H = i;
-    }
-
-    public double F() {
-        return this.I;
-    }
-
-    public void b(double d0) {
-        this.I = d0;
-    }
-
-    public void c(double d0) {
-        this.F = d0;
-    }
-
-    public void d(double d0) {
-        this.E = d0;
-    }
-
-    public double G() {
-        return this.J;
-    }
-
-    public void e(double d0) {
-        this.J = d0;
-    }
-
-    public double H() {
-        return this.K;
-    }
-
-    public void f(double d0) {
-        this.K = d0;
-    }
-
-    public int I() {
-        return this.L;
-    }
-
-    public int J() {
-        return this.M;
-    }
-
-    public void j(int i) {
-        this.L = i;
-    }
-
-    public void k(int i) {
-        this.M = i;
-    }
-
-    public EnumDifficulty getDifficulty() {
-        return this.C;
-    }
-
-    public void setDifficulty(EnumDifficulty enumdifficulty) {
-        this.C = enumdifficulty;
-        // CraftBukkit start
-        PacketPlayOutServerDifficulty packet = new PacketPlayOutServerDifficulty(this.getDifficulty(), this.isDifficultyLocked());
-        for (EntityPlayer player : (java.util.List<EntityPlayer>) (java.util.List) world.players) {
-            player.playerConnection.sendPacket(packet);
-        }
-        // CraftBukkit end
-    }
-
-    public boolean isDifficultyLocked() {
-        return this.D;
-    }
-
-    public void e(boolean flag) {
-        this.D = flag;
-    }
-
-    public void a(CrashReportSystemDetails crashreportsystemdetails) {
-        crashreportsystemdetails.a("Level seed", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.valueOf(WorldData.this.getSeed());
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level generator", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.format("ID %02d - %s, ver %d. Features enabled: %b", new Object[] { Integer.valueOf(WorldData.this.f.g()), WorldData.this.f.name(), Integer.valueOf(WorldData.this.f.getVersion()), Boolean.valueOf(WorldData.this.y)});
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level generator options", new CrashReportCallable() {
-            public String a() throws Exception {
-                return WorldData.this.g;
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level spawn location", new CrashReportCallable() {
-            public String a() throws Exception {
-                return CrashReportSystemDetails.a(WorldData.this.h, WorldData.this.i, WorldData.this.j);
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level time", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.format("%d game time, %d day time", new Object[] { Long.valueOf(WorldData.this.k), Long.valueOf(WorldData.this.l)});
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level dimension", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.valueOf(WorldData.this.p);
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level storage version", new CrashReportCallable() {
-            public String a() throws Exception {
-                String s = "Unknown?";
-
-                try {
-                    switch (WorldData.this.r) {
-                    case 19132:
-                        s = "McRegion";
-                        break;
-
-                    case 19133:
-                        s = "Anvil";
-                    }
-                } catch (Throwable throwable) {
-                    ;
-                }
-
-                return String.format("0x%05X - %s", new Object[] { Integer.valueOf(WorldData.this.r), s});
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level weather", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.format("Rain time: %d (now: %b), thunder time: %d (now: %b)", new Object[] { Integer.valueOf(WorldData.this.u), Boolean.valueOf(WorldData.this.t), Integer.valueOf(WorldData.this.w), Boolean.valueOf(WorldData.this.v)});
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-        crashreportsystemdetails.a("Level game mode", new CrashReportCallable() {
-            public String a() throws Exception {
-                return String.format("Game mode: %s (ID %d). Hardcore: %b. Cheats: %b", new Object[] { WorldData.this.x.b(), Integer.valueOf(WorldData.this.x.getId()), Boolean.valueOf(WorldData.this.z), Boolean.valueOf(WorldData.this.A)});
-            }
-
-            @Override
-            public Object call() throws Exception {
-                return this.a();
-            }
-        });
-    }
-
-    public NBTTagCompound a(DimensionManager dimensionmanager) {
-        NBTTagCompound nbttagcompound = this.N.get(dimensionmanager);
-
-        return nbttagcompound == null ? new NBTTagCompound() : nbttagcompound;
-    }
-
-    public void a(DimensionManager dimensionmanager, NBTTagCompound nbttagcompound) {
-        this.N.put(dimensionmanager, nbttagcompound);
-    }
-
-    // CraftBukkit start - Check if the name stored in NBT is the correct one
-    public void checkName( String name ) {
-        if ( !this.levelName.equals( name ) ) {
-            this.levelName = name;
-        }
-    }
-    // CraftBukkit end
-}

sources/src/main/java/net/minecraft/server/WorldServer.java

@@ -6,6 +6,7 @@ import com.google.common.util.concurrent.ListenableFuture;
 import java.io.File;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Date;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
@@ -27,10 +28,9 @@ import org.bukkit.event.weather.LightningStrikeEvent;
 // CraftBukkit end
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Expose private members<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Expose private members (core, safety issue)
+ * 2) Removed hardcore difficulty codes (slack service, feature)
  */
 public class WorldServer extends World implements IAsyncTaskHandler {
 
@@ -41,7 +41,7 @@ public class WorldServer extends World implements IAsyncTaskHandler {
     public final PlayerChunkMap manager; // Akarin - private -> public
     // private final Set<NextTickListEntry> nextTickListHash = Sets.newHashSet();
     private final HashTreeSet<NextTickListEntry> nextTickList = new HashTreeSet<NextTickListEntry>(); // CraftBukkit - HashTreeSet
-    private final Map<UUID, Entity> entitiesByUUID = Maps.newHashMap();
+    public final Map<UUID, Entity> entitiesByUUID = Maps.newHashMap(); // Paper
     public boolean savingDisabled;
     private boolean Q;
     private int emptyTime;
@@ -53,6 +53,10 @@ public class WorldServer extends World implements IAsyncTaskHandler {
     private final List<NextTickListEntry> W = Lists.newArrayList();
 
     // CraftBukkit start
+    private static final boolean DEBUG_ENTITIES = Boolean.getBoolean("debug.entities"); // Paper
+    private static Throwable getAddToWorldStackTrace(Entity entity) {
+        return new Throwable(entity + " Added to world at " + new Date());
+    }
     public final int dimension;
 
     // Add env and gen to constructor
@@ -1181,7 +1185,8 @@ public class WorldServer extends World implements IAsyncTaskHandler {
 
     private boolean j(Entity entity) {
         if (entity.dead) {
-            // WorldServer.a.warn("Tried to add entity {} but it was marked as removed already", EntityTypes.a(entity)); // CraftBukkit
+            WorldServer.a.warn("Tried to add entity {} but it was marked as removed already", EntityTypes.a(entity)); // CraftBukkit // Paper
+            if (DEBUG_ENTITIES) getAddToWorldStackTrace(entity).printStackTrace();
             return false;
         } else {
             UUID uuid = entity.getUniqueID();
@@ -1189,11 +1194,21 @@ public class WorldServer extends World implements IAsyncTaskHandler {
             if (this.entitiesByUUID.containsKey(uuid)) {
                 Entity entity1 = this.entitiesByUUID.get(uuid);
 
-                if (this.f.contains(entity1)) {
+                if (this.f.contains(entity1) || entity1.dead) { // Paper - if dupe is dead, overwrite
                     this.f.remove(entity1);
                 } else {
                     if (!(entity instanceof EntityHuman)) {
-                        // WorldServer.a.warn("Keeping entity {} that already exists with UUID {}", EntityTypes.a(entity1), uuid.toString()); // CraftBukkit
+                        if (entity.world.paperConfig.duplicateUUIDMode != com.destroystokyo.paper.PaperWorldConfig.DuplicateUUIDMode.NOTHING) {
+                             WorldServer.a.error("Keeping entity {} that already exists with UUID {}", entity1, uuid.toString()); // CraftBukkit // Paper
+                             WorldServer.a.error("Duplicate entity {} will not be added to the world. See paper.yml duplicate-uuid-resolver and set this to either regen, delete or nothing to get rid of this message", entity); // Paper
+                             if (DEBUG_ENTITIES) {
+                                 if (entity1.addedToWorldStack != null) {
+                                     entity1.addedToWorldStack.printStackTrace();
+                                 }
+                                 getAddToWorldStackTrace(entity).printStackTrace();
+                             }
+                        }
+
                         return false;
                     }
 
@@ -1211,7 +1226,24 @@ public class WorldServer extends World implements IAsyncTaskHandler {
     protected void b(Entity entity) {
         super.b(entity);
         this.entitiesById.a(entity.getId(), entity);
-        this.entitiesByUUID.put(entity.getUniqueID(), entity);
+        // Paper start
+        if (DEBUG_ENTITIES) {
+            entity.addedToWorldStack = getAddToWorldStackTrace(entity);
+        }
+        Entity old = this.entitiesByUUID.put(entity.getUniqueID(), entity);
+        if (old != null && old.getId() != entity.getId() && old.valid && entity.world.paperConfig.duplicateUUIDMode != com.destroystokyo.paper.PaperWorldConfig.DuplicateUUIDMode.NOTHING) {
+            Logger logger = LogManager.getLogger();
+            logger.error("Overwrote an existing entity " + old + " with " + entity);
+            if (DEBUG_ENTITIES) {
+                if (old.addedToWorldStack != null) {
+                    old.addedToWorldStack.printStackTrace();
+                } else {
+                    logger.error("Oddly, the old entity was not added to the world in the normal way. Plugins?");
+                }
+                entity.addedToWorldStack.printStackTrace();
+            }
+        }
+        // Paper end
         Entity[] aentity = entity.bb();
 
         if (aentity != null) {
@@ -1259,7 +1291,7 @@ public class WorldServer extends World implements IAsyncTaskHandler {
         }
         // CraftBukkit end
         if (super.strikeLightning(entity)) {
-            this.server.getPlayerList().sendPacketNearby((EntityHuman) null, entity.locX, entity.locY, entity.locZ, 512.0D, dimension, new PacketPlayOutSpawnEntityWeather(entity)); // CraftBukkit - Use dimension
+            this.server.getPlayerList().sendPacketNearby((EntityHuman) null, entity.locX, entity.locY, entity.locZ, 512.0D, this, new PacketPlayOutSpawnEntityWeather(entity)); // CraftBukkit - Use dimension, // Paper - use world instead of dimension
             return true;
         } else {
             return false;
@@ -1337,8 +1369,8 @@ public class WorldServer extends World implements IAsyncTaskHandler {
                 BlockActionData blockactiondata = (BlockActionData) iterator.next();
 
                 if (this.a(blockactiondata)) {
-                    // CraftBukkit - this.worldProvider.dimension -> this.dimension
-                    this.server.getPlayerList().sendPacketNearby((EntityHuman) null, blockactiondata.a().getX(), blockactiondata.a().getY(), blockactiondata.a().getZ(), 64.0D, dimension, new PacketPlayOutBlockAction(blockactiondata.a(), blockactiondata.d(), blockactiondata.b(), blockactiondata.c()));
+                    // CraftBukkit - this.worldProvider.dimension -> this.dimension, // Paper - dimension -> world
+                    this.server.getPlayerList().sendPacketNearby((EntityHuman) null, (double) blockactiondata.a().getX(), (double) blockactiondata.a().getY(), (double) blockactiondata.a().getZ(), 64.0D, this, new PacketPlayOutBlockAction(blockactiondata.a(), blockactiondata.d(), blockactiondata.b(), blockactiondata.c()));
                 }
             }
 

sources/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -76,10 +76,8 @@ import org.bukkit.scoreboard.Scoreboard;
 import javax.annotation.Nullable;
 
 /**
- * <b>Akarin Changes Note</b><br>
- * <br>
- * 1) Make hidden-players-set concurrent<br>
- * @author cakoyo
+ * Akarin Changes Note
+ * 1) Make hidden players thread-safe (safety issue)
  */
 @DelegateDeserialization(CraftOfflinePlayer.class)
 public class CraftPlayer extends CraftHumanEntity implements Player {
@@ -1109,10 +1107,14 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         EntityTracker tracker = ((WorldServer) entity.world).tracker;
         // Paper end
 
+        tracker.entriesLock.updateLock().lock(); // Akarin
         EntityTrackerEntry entry = tracker.trackedEntities.get(other.getId());
         if (entry != null) {
+            tracker.entriesLock.writeLock().lock(); // Akarin
             entry.clear(getHandle());
+            tracker.entriesLock.writeLock().unlock(); // Akarin
         }
+        tracker.entriesLock.updateLock().unlock(); // Akarin
 
         // Remove the hidden player from this player user list, if they're on it
         if (other.sentListPacket) {
@@ -1159,10 +1161,14 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
         getHandle().playerConnection.sendPacket(new PacketPlayOutPlayerInfo(PacketPlayOutPlayerInfo.EnumPlayerInfoAction.ADD_PLAYER, other));
 
+        tracker.entriesLock.updateLock().lock(); // Akarin
         EntityTrackerEntry entry = tracker.trackedEntities.get(other.getId());
         if (entry != null && !entry.trackedPlayers.contains(getHandle())) {
+            tracker.entriesLock.writeLock().lock(); // Akarin
             entry.updatePlayer(getHandle());
+            tracker.entriesLock.writeLock().unlock(); // Akarin
         }
+        tracker.entriesLock.updateLock().unlock(); // Akarin
     }
     // Paper start
     private void reregisterPlayer(EntityPlayer player) {
@@ -1179,11 +1185,32 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         for (EntityPlayer player : players) {
             player.getBukkitEntity().reregisterPlayer(self);
         }
+        refreshPlayer();
     }
     @Override
     public PlayerProfile getPlayerProfile() {
         return new CraftPlayerProfile(this).clone();
     }
+
+    private void refreshPlayer() {
+        EntityPlayer handle = getHandle();
+
+        Location loc = getLocation();
+
+        PlayerConnection connection = handle.playerConnection;
+        reregisterPlayer(handle);
+
+        //Respawn the player then update their position and selected slot
+        connection.sendPacket(new PacketPlayOutRespawn(handle.dimension, handle.world.getDifficulty(), handle.world.getWorldData().getType(), handle.playerInteractManager.getGameMode()));
+        handle.updateAbilities();
+        connection.sendPacket(new PacketPlayOutPosition(loc.getX(), loc.getY(), loc.getZ(), loc.getYaw(), loc.getPitch(), new HashSet<>(), 0));
+        MinecraftServer.getServer().getPlayerList().updateClient(handle);
+
+        if (this.isOp()) {
+            this.setOp(false);
+            this.setOp(true);
+        }
+    }
     // Paper end
 
     public void removeDisconnectingPlayer(Player player) {

sources/src/main/resources/mixins.akarin.core.json

@@ -15,27 +15,25 @@
         
         "core.MixinWorld",
         "core.MixinMCUtil",
-        "core.MixinPlayerList",
         "core.MixinCommandBan",
         "core.MixinCommandKick",
         "core.MixinCraftServer",
         "core.MixinWorldServer",
+        "core.MixinFileIOThread",
+        "core.MixinWorldManager",
         "core.MixinCommandBanIp",
         "core.MixinChunkSection",
         "core.MixinAsyncCatcher",
         "core.MixinTimingHandler",
-        "core.MonsterEggGuardian",
         "core.MixinVersionCommand",
         "core.MixinMinecraftServer",
         "core.MixinChunkIOExecutor",
         "core.MixinPlayerConnectionUtils",
         
-        "cps.MixinCraftWorld",
-        "cps.MixinChunkProviderServer",
-        
         "nsc.OptimisticNetworkManager",
         "nsc.NonblockingServerConnection",
         
+        "optimization.MixinEntity",
         "optimization.WeakBigTree",
         "optimization.WeakEnchantmentManager",
         "optimization.MixinEntityHorseAbstract",

sources/src/main/resources/mixins.akarin.optimization.chunk.json

@@ -5,11 +5,7 @@
     "target": "@env(DEFAULT)",
     "compatibilityLevel": "JAVA_8",
     "server": [
-        "cps.MixinChunk",
-        
-        "lighting.MixinChunk",
-        "lighting.MixinWorld",
-        "lighting.MixinWorldServer",
-        "lighting.MixinChunkProviderServer",
+        "cps.MixinCraftWorld",
+        "cps.MixinChunkProviderServer",
     ]
 }