Leaf/leaf-server/paper-patches/features/0032-Virtual-Thread-for-async-scheduler.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: nostalfinals <yuu8583@proton.me>
Date: Tue, 12 Mar 2024 00:36:29 +0800
Subject: [PATCH] Virtual Thread for async scheduler


diff --git a/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java b/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
index 0ca279fb71d39c81b1f608e0ee9ba3e498d55fa3..1aaccc688d246201db141a0d5e2c68d0dd4069b2 100644
--- a/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
+++ b/src/main/java/org/bukkit/craftbukkit/scheduler/CraftAsyncScheduler.java
@@ -38,17 +38,40 @@ import java.util.concurrent.TimeUnit;
 
 public class CraftAsyncScheduler extends CraftScheduler {
 
-    private final ThreadPoolExecutor executor = new ThreadPoolExecutor(
-            4, Integer.MAX_VALUE,30L, TimeUnit.SECONDS, new SynchronousQueue<>(),
-            new ThreadFactoryBuilder().setNameFormat("Craft Scheduler Thread - %1$d").build());
+    private final org.apache.logging.log4j.Logger LOGGER = org.apache.logging.log4j.LogManager.getLogger(getClass().getName()); // Leaf - Class logger
+    private final Executor executor; // Leaf - use super class
     private final Executor management = Executors.newSingleThreadExecutor(new ThreadFactoryBuilder()
             .setNameFormat("Craft Async Scheduler Management Thread").build());
     private final List<CraftTask> temp = new ArrayList<>();
 
     CraftAsyncScheduler() {
         super(true);
-        executor.allowCoreThreadTimeOut(true);
-        executor.prestartAllCoreThreads();
+
+        // Leaf start - Ability to use Virtual Thread for async scheduler
+        if (org.dreeam.leaf.config.modules.opt.VT4BukkitScheduler.enabled) {
+            executor = new ThreadPoolExecutor(
+                    0, Integer.MAX_VALUE, 10L, TimeUnit.SECONDS, new SynchronousQueue<>(), // Use 10s for keepalive time
+                    Thread.ofVirtual()
+                            .name("Craft Scheduler Thread - ", 0)
+                            .uncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER))
+                            .factory()
+            );
+
+            return;
+        }
+
+        executor = new ThreadPoolExecutor(
+                4, Integer.MAX_VALUE, 30L, TimeUnit.SECONDS, new SynchronousQueue<>(),
+                new ThreadFactoryBuilder()
+                        .setNameFormat("Craft Scheduler Thread - %1$d")
+                        .setUncaughtExceptionHandler(new net.minecraft.DefaultUncaughtExceptionHandlerWithName(net.minecraft.server.MinecraftServer.LOGGER))
+                        .build());
+
+        var threadPoolExecutor = (ThreadPoolExecutor) executor;
+
+        threadPoolExecutor.allowCoreThreadTimeOut(true);
+        threadPoolExecutor.prestartAllCoreThreads();
+        // Leaf end - Ability to use Virtual Thread for async scheduler
     }
 
     @Override