From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: ishland <ishlandmc@yeah.net>
Date: Sat, 12 Mar 2022 16:03:35 +0100
Subject: [PATCH] vmp: use linked map for entity trackers for faster iteration

Copyright (c) 2021-2022 ishland

Original code by RelativityMC, licensed under MIT
You can find the original code on https://github.com/RelativityMC/VMP-fabric (Yarn mappings)

diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
index b9d4878dd629886c4ef3e29ff1b729571d81d785..629ee5ece4819608fe12db64b817edeeb777d1fc 100644
--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
+++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
@@ -111,6 +111,7 @@ import org.bukkit.craftbukkit.generator.CustomChunkGenerator;
 import org.bukkit.entity.Player;
 // CraftBukkit end
 import it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet; // Paper
+import it.unimi.dsi.fastutil.ints.Int2ObjectLinkedOpenHashMap; // Mirai - vmp: use linked map for entity trackers for faster iteration
 
 public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider {
 
@@ -416,7 +417,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
         this.toDrop = new LongOpenHashSet();
         this.tickingGenerated = new AtomicInteger();
         this.playerMap = new PlayerMap();
-        this.entityMap = new Int2ObjectOpenHashMap();
+        this.entityMap = new Int2ObjectLinkedOpenHashMap<>(); // Mirai - vmp: use linked map for entity trackers for faster iteration
         this.chunkTypeCache = new Long2ByteOpenHashMap();
         this.chunkSaveCooldowns = new Long2LongOpenHashMap();
         this.unloadQueue = new com.destroystokyo.paper.utils.CachedSizeConcurrentLinkedQueue<>(); // Paper - need constant-time size()