Paper/patches/server/0721-Do-not-allow-the-server-to-unload-chunks-at-request-.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Thu, 11 Mar 2021 02:32:30 -0800
Subject: [PATCH] Do not allow the server to unload chunks at request of
 plugins

In general the chunk system is not well suited for this behavior,
especially if it is called during a chunk load. The chunks pushed
to be unloaded will simply be unloaded next tick, rather than
immediately.

diff --git a/src/main/java/net/minecraft/server/level/ServerChunkCache.java b/src/main/java/net/minecraft/server/level/ServerChunkCache.java
index 15b275ee91451478d1c55eae0d20e0e8f36f3a0f..dd4656f0b9d7740ab449ede2588df64e647fab40 100644
--- a/src/main/java/net/minecraft/server/level/ServerChunkCache.java
+++ b/src/main/java/net/minecraft/server/level/ServerChunkCache.java
@@ -694,6 +694,7 @@ public class ServerChunkCache extends ChunkSource {
 
     // CraftBukkit start - modelled on below
     public void purgeUnload() {
+        if (true) return; // Paper - tickets will be removed later, this behavior isn't really well accounted for by the chunk system
         this.level.getProfiler().push("purge");
         this.distanceManager.purgeStaleTickets();
         this.runDistanceManagerUpdates();