mirror of
https://github.com/PaperMC/Paper.git
synced 2024-11-22 23:29:32 +01:00
54 lines
2.9 KiB
Diff
54 lines
2.9 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 4232ce05ad7dd122a78a04ccef3b59d4caf542df..2cce259c738de2680e219d30dc3020458f4442d6 100644
|
|
--- a/src/main/java/com/mojang/datafixers/DataFixerBuilder.java
|
|
+++ b/src/main/java/com/mojang/datafixers/DataFixerBuilder.java
|
|
@@ -29,8 +29,10 @@ public class DataFixerBuilder {
|
|
private final Int2ObjectSortedMap<Schema> schemas = new Int2ObjectAVLTreeMap<>();
|
|
private final List<DataFix> globalList = new ArrayList<>();
|
|
private final IntSortedSet fixerVersions = new IntAVLTreeSet();
|
|
+ private final int minDataFixPrecacheVersion; // Paper - Perf: Cache DataFixerUpper Rewrite Rules on demand
|
|
|
|
public DataFixerBuilder(final int dataVersion) {
|
|
+ minDataFixPrecacheVersion = Integer.getInteger("Paper.minPrecachedDatafixVersion", dataVersion+1) * 10; // Paper - Perf: default to precache nothing - mojang stores versions * 10 to allow for 'sub versions'
|
|
this.dataVersion = dataVersion;
|
|
}
|
|
|
|
@@ -88,6 +90,7 @@ public class DataFixerBuilder {
|
|
final IntIterator iterator = fixerUpper.fixerVersions().iterator();
|
|
while (iterator.hasNext()) {
|
|
final int versionKey = iterator.nextInt();
|
|
+ if (versionKey < minDataFixPrecacheVersion) continue; // Paper - Perf: Cache DataFixerUpper Rewrite Rules on demand
|
|
final Schema schema = schemas.get(versionKey);
|
|
for (final String typeName : schema.types()) {
|
|
if (!requiredTypeNames.contains(typeName)) {
|