From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Cryptite <cryptite@gmail.com>
Date: Mon, 26 Jun 2023 16:45:00 -0500
Subject: [PATCH] Save DimensionDataStorage async


diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index ad868de68ecc5eee9701f8fe3d48e9fb3ed422d8..ef2d88765dbcc36ca3a1f36101e389799241bcde 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -2142,8 +2142,8 @@ public class ServerLevel extends Level implements WorldGenLevel {
         if (existing == null && !storage.cache.containsKey(id)) {
             final net.minecraft.world.level.saveddata.SavedData.Factory<MapItemSavedData> factory = MapItemSavedData.factory();
             final MapItemSavedData map = storage.readSavedData(factory.deserializer(), factory.type(), id);
-            storage.cache.put(id, map);
             if (map != null) {
+                storage.cache.put(id, map);
                 map.id = id;
                 new MapInitializeEvent(map.mapView).callEvent();
                 return map;
diff --git a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
index d051e8c1db6b5c42b8df0be54d9d48ba0e7b0077..f90f7fc66396091bdeb98bc3271b68bca693ee15 100644
--- a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
+++ b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
@@ -9,6 +9,8 @@ import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.PushbackInputStream;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Function;
 import javax.annotation.Nullable;
 import net.minecraft.SharedConstants;
@@ -18,11 +20,12 @@ import net.minecraft.nbt.NbtIo;
 import net.minecraft.nbt.NbtUtils;
 import net.minecraft.util.datafix.DataFixTypes;
 import net.minecraft.world.level.saveddata.SavedData;
+import org.bukkit.Bukkit;
 import org.slf4j.Logger;
 
 public class DimensionDataStorage {
     private static final Logger LOGGER = LogUtils.getLogger();
-    public final Map<String, SavedData> cache = Maps.newHashMap();
+    public final Map<String, SavedData> cache = new ConcurrentHashMap<>();
     private final DataFixer fixerUpper;
     private final File dataFolder;
 
@@ -51,7 +54,7 @@ public class DimensionDataStorage {
         SavedData savedData = this.cache.get(id);
         if (savedData == null && !this.cache.containsKey(id)) {
             savedData = this.readSavedData(type.deserializer(), type.type(), id);
-            this.cache.put(id, savedData);
+            if (savedData != null) this.cache.put(id, savedData);
         }
 
         return (T)savedData;
@@ -119,11 +122,12 @@ public class DimensionDataStorage {
     }
 
     public void save() {
-        this.cache.forEach((id, state) -> {
+        // Slice start - run async
+        CompletableFuture.runAsync(() -> this.cache.forEach((id, state) -> {
             if (state != null) {
                 state.save(this.getDataFile(id));
             }
-
-        });
+        }));
+        // Slice end
     }
 }