From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Thu, 1 Dec 2022 14:40:03 +0100
Subject: [PATCH] Use linked map for entity trackers

License: MIT (https://opensource.org/licenses/MIT)
Gale - https://galemc.org

This patch is based on the following mixin:
"com/ishland/vmp/mixins/entitytracker/MixinThreadedAnvilChunkStorage.java"
By: ishland <ishlandmc@yeah.net>
As part of: VMP (https://github.com/RelativityMC/VMP-fabric)
Licensed under: MIT (https://opensource.org/licenses/MIT)

diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
index 41140fbf32fc4db1b2460e453420e538290f4f99..baa6aaa495c2a9d4d2f6a62527881b9442fcaeea 100644
--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
+++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
@@ -14,6 +14,7 @@ import com.mojang.datafixers.util.Either;
 import com.mojang.logging.LogUtils;
 import com.mojang.serialization.DataResult;
 import com.mojang.serialization.JsonOps;
+import it.unimi.dsi.fastutil.ints.Int2ObjectLinkedOpenHashMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.longs.Long2ByteMap;
@@ -294,7 +295,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
         // Paper - rewrite chunk system
         this.tickingGenerated = new AtomicInteger();
         this.playerMap = new PlayerMap();
-        this.entityMap = new Int2ObjectOpenHashMap();
+        this.entityMap = new Int2ObjectLinkedOpenHashMap(); // Gale - VMP - use linked map for entity trackers - provides faster iteration
         this.chunkTypeCache = new Long2ByteOpenHashMap();
         this.chunkSaveCooldowns = new Long2LongOpenHashMap();
         this.unloadQueue = Queues.newConcurrentLinkedQueue();