Paper/patches/server/0668-Execute-chunk-tasks-fairly-for-worlds-while-waiting-.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Tue, 28 Dec 2021 07:19:01 -0800
Subject: [PATCH] Execute chunk tasks fairly for worlds while waiting for next
 tick

Currently, only the first world would have had tasks executed.
This might result in chunks loading far slower in the nether,
for example.

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 22f8e49536658fabe6136dbeec6b77eaf4ae5ee8..e5017b66b6b8b5f17fc49f0fbc5d342241cd9cad 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -1371,6 +1371,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         if (super.pollTask()) {
             return true;
         } else {
+            boolean ret = false; // Paper - force execution of all worlds, do not just bias the first
             if (this.tickRateManager.isSprinting() || this.haveTime()) {
                 Iterator iterator = this.getAllLevels().iterator();
 
@@ -1378,12 +1379,12 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                     ServerLevel worldserver = (ServerLevel) iterator.next();
 
                     if (worldserver.getChunkSource().pollTask()) {
-                        return true;
+                        ret = true; // Paper - force execution of all worlds, do not just bias the first
                     }
                 }
             }
 
-            return false;
+            return ret; // Paper - force execution of all worlds, do not just bias the first
         }
     }