PaperMC/patches/server/0739-Optimize-HashMapPalette.patch
Nassim Jahnke c0936a71bd
Updated Upstream (Bukkit/CraftBukkit/Spigot) (#9440)
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Bukkit Changes:
01aa02eb PR-858: Add LivingEntity#playHurtAnimation()
9421320f PR-884: Refinements to new ban API for improved compatibility and correctness
37a60b45 SPIGOT-6455, SPIGOT-7030, PR-750: Improve ban API
4eeb174b All smithing inventories are now the new smithing inventory
f2bb168e PR-880: Add methods to get/set FallingBlock CancelDrop
e7a807fa PR-879: Add Player#sendHealthUpdate()
692b8e96 SPIGOT-7370: Remove float value conversion in plugin.yml
2d033390 SPIGOT-7403: Add direct API for waxed signs
16a08373 PR-876: Add missing Raider API and 'no action ticks'

CraftBukkit Changes:
b60a95c8c PR-1189: Add LivingEntity#playHurtAnimation()
95c335c63 PR-1226: Fix VehicleEnterEvent not being called for certain entities
0a0fc3bee PR-1227: Refinements to new ban API for improved compatibility and correctness
0d0b1e5dc Revert bad change to PathfinderGoalSit causing all cats to sit
648196070 SPIGOT-6455, SPIGOT-7030, PR-1054: Improve ban API
31fe848d6 All smithing inventories are now the new smithing inventory
9a919a143 SPIGOT-7416: SmithItemEvent not firing in Smithing Table
9f64f0d22 PR-1221: Add methods to get/set FallingBlock CancelDrop
3be9ac171 PR-1220: Add Player#sendHealthUpdate()
c1279f775 PR-1209: Clean up various patches
c432e4397 Fix Raider#setCelebrating() implementation
504d96665 SPIGOT-7403: Add direct API for waxed signs
c68c1f1b3 PR-1216: Add missing Raider API and 'no action ticks'
85b89c3dd Increase outdated build delay

Spigot Changes:
9ebce8af Rebuild patches
64b565e6 Rebuild patches
2023-07-04 10:22:56 +02:00

57 lines
3.2 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: stonar96 <minecraft.stonar96@gmail.com>
Date: Sun, 17 Jan 2021 01:11:36 +0100
Subject: [PATCH] Optimize HashMapPalette
HashMapPalette uses an instance of CrudeIncrementalIntIdentityHashBiMap
internally. A Palette has a preset maximum size = 1 << bits.
CrudeIncrementalIntIdentityHashBiMap has an initial size but is
automatically resized. The CrudeIncrementalIntIdentityHashBiMap is created
with the maximum size in the constructor of HashMapPalette, with the aim
that it doesn't need to be resized anymore. However, there are two things
that I think Mojang hasn't considered here:
1) The CrudeIncrementalIntIdentityHashBiMap is resized, when its initial
size is reached and not the next time, when a further object is added.
2) HashMapPalette adds objects (unnecessarily) before checking if the
initial size of CrudeIncrementalIntIdentityHashBiMap is reached.
This means to actually avoid resize operations in
CrudeIncrementalIntIdentityHashBiMap, one has to add 2 to the initial size
or add 1 and check the size before adding objects. This commit implements
the second approach. Note that this isn't only an optimization but also
makes async reads of Palettes fail-safe. An async read while the
CrudeIncrementalIntIdentityHashBiMap is resized is fatal and can even lead
to corrupted data. This is also something that Anti-Xray is currently
relying on.
diff --git a/src/main/java/net/minecraft/world/level/chunk/HashMapPalette.java b/src/main/java/net/minecraft/world/level/chunk/HashMapPalette.java
index a6d0008636f72ff6614eda4b1fa856798e6b46fd..50580313a1e224a9569e343ccf4aa0c00b906a30 100644
--- a/src/main/java/net/minecraft/world/level/chunk/HashMapPalette.java
+++ b/src/main/java/net/minecraft/world/level/chunk/HashMapPalette.java
@@ -19,7 +19,7 @@ public class HashMapPalette<T> implements Palette<T> {
}
public HashMapPalette(IdMap<T> idList, int indexBits, PaletteResize<T> listener) {
- this(idList, indexBits, listener, CrudeIncrementalIntIdentityHashBiMap.create(1 << indexBits));
+ this(idList, indexBits, listener, CrudeIncrementalIntIdentityHashBiMap.create((1 << indexBits) + 1)); // Paper - Avoid unnecessary resize operation in CrudeIncrementalIntIdentityHashBiMap
}
private HashMapPalette(IdMap<T> idList, int indexBits, PaletteResize<T> listener, CrudeIncrementalIntIdentityHashBiMap<T> map) {
@@ -37,10 +37,16 @@ public class HashMapPalette<T> implements Palette<T> {
public int idFor(T object) {
int i = this.values.getId(object);
if (i == -1) {
- i = this.values.add(object);
- if (i >= 1 << this.bits) {
+ // Paper start - Avoid unnecessary resize operation in CrudeIncrementalIntIdentityHashBiMap and optimize
+ // We use size() instead of the result from add(K)
+ // This avoids adding another object unnecessarily
+ // Without this change, + 2 would be required in the constructor
+ if (this.values.size() >= 1 << this.bits) {
i = this.resizeHandler.onResize(this.bits + 1, object);
+ } else {
+ i = this.values.add(object);
}
+ // Paper end
}
return i;