From 7fca1b3434f57de370ca948b5d846262a058c9bb Mon Sep 17 00:00:00 2001 From: Aikar Date: Mon, 17 Sep 2018 23:37:31 -0400 Subject: [PATCH] Optimize Server World Map Minecraft moved worlds to a hashmap in 1.13.1. This creates inconsistent order for iteration of the map. This patch restores World management to be back as an Array. .values() will allow us to iterate as it was pre 1.13.1 by ArrayList, giving consistent ordering and effecient iteration performance. KeySet and EntrySet iteration is proxied to the List iterator, and should retain manipulation behavior but nothing should be doing that. Getting a World by dimension ID is now back a constant time operation. Hopefully no other plugins try to mess with this map, as we are only handling known NMS used methods, but we can add more if naughty plugins are found later. diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldMap.java b/src/main/java/com/destroystokyo/paper/PaperWorldMap.java new file mode 100644 index 0000000000..6bb2f98b45 --- /dev/null +++ b/src/main/java/com/destroystokyo/paper/PaperWorldMap.java @@ -0,0 +1,191 @@ +package com.destroystokyo.paper; + +import net.minecraft.server.DimensionManager; +import net.minecraft.server.WorldServer; + +import javax.annotation.Nonnull; +import java.util.AbstractSet; +import java.util.ArrayList; +import java.util.Collection; +import java.util.HashMap; +import java.util.Iterator; +import java.util.List; +import java.util.Map; +import java.util.Set; + +public class PaperWorldMap extends HashMap { + private final List worlds = new ArrayList<>(); + private final List worldsIterable = new ArrayList() { + @Override + public Iterator iterator() { + Iterator iterator = super.iterator(); + return new Iterator() { + private WorldServer last; + + @Override + public boolean hasNext() { + return iterator.hasNext(); + } + + @Override + public WorldServer next() { + this.last = iterator.next(); + return last; + } + + @Override + public void remove() { + worlds.set(last.worldProvider.getDimensionManager().getDimensionID() + 1, null); + } + }; + } + }; + @Override + public int size() { + return worldsIterable.size(); + } + + @Override + public boolean isEmpty() { + return worldsIterable.isEmpty(); + } + + @Override + public WorldServer get(Object key) { + // Will hit the below method + return key instanceof DimensionManager ? get((DimensionManager) key) : null; + } + + public WorldServer get(DimensionManager key) { + int id = key.getDimensionID()+1; + return worlds.size() > id ? worlds.get(id) : null; + } + + @Override + public boolean containsKey(Object key) { + // will hit below method + return key instanceof DimensionManager && containsKey((DimensionManager) key); + } + public boolean containsKey(DimensionManager key) { + return get(key) != null; + } + + @Override + public WorldServer put(DimensionManager key, WorldServer value) { + while (worlds.size() <= key.getDimensionID()+1) { + worlds.add(null); + } + WorldServer old = worlds.set(key.getDimensionID()+1, value); + if (old != null) { + worldsIterable.remove(old); + } + worldsIterable.add(value); + return old; + } + + @Override + public void putAll(Map m) { + for (Entry e : m.entrySet()) { + put(e.getKey(), e.getValue()); + } + } + + @Override + public WorldServer remove(Object key) { + return key instanceof DimensionManager ? remove((DimensionManager) key) : null; + } + + public WorldServer remove(DimensionManager key) { + WorldServer old; + if (key.getDimensionID()+1 == worlds.size() - 1) { + old = worlds.remove(key.getDimensionID()+1); + } else { + old = worlds.set(key.getDimensionID() + 1, null); + } + if (old != null) { + worldsIterable.remove(old); + } + return old; + } + + @Override + public void clear() { + throw new RuntimeException("What the hell are you doing?"); + } + + @Override + public boolean containsValue(Object value) { + return value instanceof WorldServer && get(((WorldServer) value).worldProvider.getDimensionManager()) != null; + } + + @Nonnull + @Override + public Set keySet() { + return new AbstractSet() { + @Override + public Iterator iterator() { + Iterator iterator = worldsIterable.iterator(); + return new Iterator() { + + @Override + public boolean hasNext() { + return iterator.hasNext(); + } + + @Override + public DimensionManager next() { + return iterator.next().worldProvider.getDimensionManager(); + } + + @Override + public void remove() { + iterator.remove(); + } + }; + } + + @Override + public int size() { + return worlds.size(); + } + }; + } + + @Override + public Collection values() { + return worldsIterable; + } + + @Override + public Set> entrySet() { + return new AbstractSet>() { + @Override + public Iterator> iterator() { + Iterator iterator = worldsIterable.iterator(); + return new Iterator>() { + + @Override + public boolean hasNext() { + return iterator.hasNext(); + } + + @Override + public Entry next() { + WorldServer entry = iterator.next(); + return new SimpleEntry<>(entry.worldProvider.getDimensionManager(), entry); + } + + @Override + public void remove() { + iterator.remove(); + } + }; + } + + @Override + public int size() { + return worldsIterable.size(); + } + }; + } +} diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java index de423de63b..a5447c6501 100644 --- a/src/main/java/net/minecraft/server/MinecraftServer.java +++ b/src/main/java/net/minecraft/server/MinecraftServer.java @@ -88,7 +88,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant worldServer = Maps.newLinkedHashMap(); // CraftBukkit - keep order, k+v already use identity methods + public final Map worldServer = new com.destroystokyo.paper.PaperWorldMap(); // Paper; private PlayerList playerList; private volatile boolean isRunning = true; private volatile boolean isRestarting = false; // Paper - flag to signify we're attempting to restart @@ -451,7 +451,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant