From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: HaHaWTH <102713261+HaHaWTH@users.noreply.github.com>
Date: Fri, 14 Jun 2024 17:34:17 -0400
Subject: [PATCH] Fix-MC-183518

Related MC issue: https://bugs.mojang.com/browse/MC-183518

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 2445d549fbf972620f2cc13860f826562ff3f4d0..9dce5c34f67799285ee395a9c5d0db5ee6319536 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -311,6 +311,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
     public gg.pufferfish.pufferfish.util.AsyncExecutor mobSpawnExecutor = new gg.pufferfish.pufferfish.util.AsyncExecutor("Leaf Async Mob Spawn Thread"); // Pufferfish - optimize mob spawning // Leaf - Unify thread name
     public final Set<Entity> entitiesWithScheduledTasks = java.util.concurrent.ConcurrentHashMap.newKeySet(); // SparklyPaper - skip EntityScheduler's executeTick checks if there isn't any tasks to be run (concurrent because plugins may schedule tasks async)
+    private boolean waitingForNextTick = false; // Leaf - Fix MC-183518
 
     public static <S extends MinecraftServer> S spin(Function<Thread, S> serverFactory) {
         AtomicReference<S> atomicreference = new AtomicReference();
@@ -1494,9 +1495,16 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
     protected void waitUntilNextTick() {
         long tickOversleepStart = System.nanoTime(); // Gale - YAPFA - last tick time
-        this.managedBlock(() -> {
-            return !this.canSleepForTickNoOversleep(); // Paper - move oversleep into full server tick
-        });
+        // Leaf start - Fix MC-183518
+        this.waitingForNextTick = true;
+        try {
+            this.managedBlock(() -> {
+                return !this.canSleepForTickNoOversleep(); // Paper - move oversleep into full server tick
+            });
+        } finally {
+            this.waitingForNextTick = false;
+        }
+        // Leaf end - Fix MC-183518
         lastTickOversleepTime = (System.nanoTime() - tickOversleepStart) / 1000000L; // Gale - YAPFA - last tick time
     }
 
@@ -1505,7 +1513,10 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         boolean flag = this.isTickTimeLoggingEnabled();
         long i = flag ? Util.getNanos() : 0L;
 
-        super.waitForTasks();
+        // Leaf start - Fix MC-183518
+        long ms = this.waitingForNextTick ? this.nextTickTimeNanos - Util.getNanos() : 100_000L;
+        java.util.concurrent.locks.LockSupport.parkNanos("waiting for tasks", ms);
+        // Leaf end - Fix MC-183518
         if (flag) {
             this.idleTimeNanos += Util.getNanos() - i;
         }