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 2559a40546701fefa7f28603cb637108bfc659da..f728c5b75ee7db5522e558891988079c52df5e72 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
         }
     }