From ca605f00544babfb805f1f59e6b12f388bf26f99 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 30 Mar 2016 02:13:24 -0400
Subject: [PATCH] Use Optimized Collections

Swap out CraftBukkit LongObjectHashMap with Long2ObjectOpenHashMap
Swap out Integer key HashMap for a Int2ObjectOpenHashMap For ChunkProviderServer

Amaranth, the creator of LongObjectHashMap, tested it vs fastutil and determined fastutil to be 3x faster
and could not create anything faster than fastutil.

These collections are super fast as seen
http://java-performance.info/hashmap-overview-jdk-fastutil-goldman-sachs-hppc-koloboke-trove-january-2015/

diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index 3d36d7a..8ee8e80 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -24,7 +24,7 @@ import org.bukkit.event.world.ChunkUnloadEvent;
 public class ChunkProviderServer implements IChunkProvider {
 
     private static final Logger a = LogManager.getLogger();
-    public final Set<Long> unloadQueue = Sets.newHashSet(); // PAIL: private -> public
+    public final it.unimi.dsi.fastutil.longs.LongSet unloadQueue = new it.unimi.dsi.fastutil.longs.LongArraySet(); // PAIL: private -> public // Paper
     public final ChunkGenerator chunkGenerator;
     private final IChunkLoader chunkLoader;
     // Paper start
diff --git a/src/main/java/net/minecraft/server/DataWatcher.java b/src/main/java/net/minecraft/server/DataWatcher.java
index ec77a5c..86ad41d 100644
--- a/src/main/java/net/minecraft/server/DataWatcher.java
+++ b/src/main/java/net/minecraft/server/DataWatcher.java
@@ -12,13 +12,14 @@ import java.util.Map;
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import javax.annotation.Nullable;
+import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap; // Paper
 import org.apache.commons.lang3.ObjectUtils;
 
 public class DataWatcher {
 
     private static final Map<Class<? extends Entity>, Integer> a = Maps.newHashMap();
     private final Entity b;
-    private final Map<Integer, DataWatcher.Item<?>> c = Maps.newHashMap();
+    private final Map<Integer, DataWatcher.Item<?>> c = new Int2ObjectOpenHashMap<>(); // Paper
     private final ReadWriteLock d = new ReentrantReadWriteLock();
     private boolean e = true;
     private boolean f;
-- 
2.8.2