Paper/patches/server/0458-Cache-DataFixerUpper-Rewrite-Rules-on-demand.patch
Jake Potrebic de04cbced5
Updated Upstream (Bukkit/CraftBukkit) (#10034)
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:
f29cb801 Separate checkstyle-suppressions file is not required
86f99bbe SPIGOT-7540, PR-946: Add ServerTickManager API
d4119585 SPIGOT-6903, PR-945: Add BlockData#getMapColor
b7a2ed41 SPIGOT-7530, PR-947: Add Player#removeResourcePack
9dd56255 SPIGOT-7527, PR-944: Add WindCharge#explode()
994a6163 Attempt upgrade of resolver libraries

CraftBukkit Changes:
b3b43a6ad Add Checkstyle check for unused imports
13fb3358e SPIGOT-7544: Scoreboard#getEntries() doesn't get entries but class names
3dda99c06 SPIGOT-7540, PR-1312: Add ServerTickManager API
2ab4508c0 SPIGOT-6903, PR-1311: Add BlockData#getMapColor
1dbdbbed4 PR-1238: Remove unnecessary sign ticking
659728d2a MC-264285, SPIGOT-7439, PR-1237: Fix unbreakable flint and steel is completely consumed while igniting creeper
e37e29ce0 Increase outdated build delay
c00438b39 SPIGOT-7530, PR-1313: Add Player#removeResourcePack
492dd80ce SPIGOT-7527, PR-1310: Add WindCharge#explode()
e11fbb9d7 Upgrade MySQL driver
9f3a0bd2a Attempt upgrade of resolver libraries
60d16d7ca PR-1306: Centralize Bukkit and Minecraft entity conversion

Spigot Changes:
06d602e7 Rebuild patches
2023-12-16 18:09:28 -08:00

55 lines
2.8 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 12 Sep 2020 17:21:38 -0400
Subject: [PATCH] Cache DataFixerUpper Rewrite Rules on demand
Mojang precaches every single potential rewrite rule that could ever
exist on server startup. This includes rules from all the way back to versions from 6+ years ago.
This is the source of why the server hogs every CPU core at 100% every start.
For anyone who hard resets for updates or has force upgraded their entire world, this
results in completely wasted cpu cycles.
This massive CPU usage also delays server startup time.
We improve this by making "min version to precache" that defaults to a future version
so that no rewrite rules are precached.
someone who expects to be converting a lot chunks could theoretically set
-DPaper.minPrecachedDatafixVersion=<dataVersionConvertingFrom> as a startup
parameter and only build from that point on.
However this will likely never be needed as the server will still run
the same cache logic on demand when it's actually needed. The only
cost would be some delay on the FIRST chunk conversion, but paper already
runs chunk conversions on another thread so this will likely never be
a concern for TPS.
This patch will significantly reduce CPU use on startup, reduce memory usage,
and improve server startup time.
diff --git a/src/main/java/com/mojang/datafixers/DataFixerBuilder.java b/src/main/java/com/mojang/datafixers/DataFixerBuilder.java
index cd812f3fe362de5ddc414862dedab2e9727ca776..f6598fcf4ed1bd61e1c87cd7107869d49ffe4566 100644
--- a/src/main/java/com/mojang/datafixers/DataFixerBuilder.java
+++ b/src/main/java/com/mojang/datafixers/DataFixerBuilder.java
@@ -30,8 +30,10 @@ public class DataFixerBuilder {
private final Int2ObjectSortedMap<Schema> schemas = new Int2ObjectAVLTreeMap<>();
private final List<DataFix> globalList = Lists.newArrayList();
private final IntSortedSet fixerVersions = new IntAVLTreeSet();
+ private final int minDataFixPrecacheVersion; // Paper
public DataFixerBuilder(final int dataVersion) {
+ minDataFixPrecacheVersion = Integer.getInteger("Paper.minPrecachedDatafixVersion", dataVersion+1) * 10; // Paper - default to precache nothing - mojang stores versions * 10 to allow for 'sub versions'
this.dataVersion = dataVersion;
}
@@ -78,6 +80,7 @@ public class DataFixerBuilder {
final IntBidirectionalIterator iterator = fixerUpper.fixerVersions().iterator();
while (iterator.hasNext()) {
final int versionKey = iterator.nextInt();
+ if (versionKey < minDataFixPrecacheVersion) continue; // Paper
final Schema schema = schemas.get(versionKey);
for (final String typeName : schema.types()) {
if (!requiredTypeNames.contains(typeName)) {