papermc/Spigot-Server-Patches/0404-Optimise-getChunkAt-calls-for-loaded-chunks.patch
Aikar 4768e3c4ed
Optimize Loaded Chunks Cache Lookups
Reduces number of instructions a chunk lookup does
when accessing the last chunk cache. This reduces amount of work and opcodes
and allows better inlining.

In lots of profiling comparisons, this optimization was able to reduce the
cost of repeated chunk lookups that hit the cache pretty significantly.
2021-01-09 18:09:09 -05:00

66 lines
2.8 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sat, 25 Jan 2020 17:04:35 -0800
Subject: [PATCH] Optimise getChunkAt calls for loaded chunks
bypass the need to get a player chunk, then get the either,
then unwrap it...
diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index 2fad6a79ee977c2712c55433bde8eca524d09ba7..37ea114deba56efa6692a5e2290c2ef2d4d70ec8 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -439,6 +439,12 @@ public class ChunkProviderServer extends IChunkProvider {
return this.getChunkAt(i, j, chunkstatus, flag);
}, this.serverThreadQueue).join();
} else {
+ // Paper start - optimise for loaded chunks
+ Chunk ifLoaded = this.getChunkAtIfLoadedMainThread(i, j);
+ if (ifLoaded != null) {
+ return ifLoaded;
+ }
+ // Paper end
GameProfilerFiller gameprofilerfiller = this.world.getMethodProfiler();
gameprofilerfiller.c("getChunk");
@@ -489,39 +495,7 @@ public class ChunkProviderServer extends IChunkProvider {
if (Thread.currentThread() != this.serverThread) {
return null;
} else {
- this.world.getMethodProfiler().c("getChunkNow");
- long k = ChunkCoordIntPair.pair(i, j);
-
- for (int l = 0; l < 4; ++l) {
- if (k == this.cachePos[l] && this.cacheStatus[l] == ChunkStatus.FULL) {
- IChunkAccess ichunkaccess = this.cacheChunk[l];
-
- return ichunkaccess instanceof Chunk ? (Chunk) ichunkaccess : null;
- }
- }
-
- PlayerChunk playerchunk = this.getChunk(k);
-
- if (playerchunk == null) {
- return null;
- } else {
- Either<IChunkAccess, PlayerChunk.Failure> either = (Either) playerchunk.b(ChunkStatus.FULL).getNow(null); // CraftBukkit - decompile error
-
- if (either == null) {
- return null;
- } else {
- IChunkAccess ichunkaccess1 = (IChunkAccess) either.left().orElse(null); // CraftBukkit - decompile error
-
- if (ichunkaccess1 != null) {
- this.a(k, ichunkaccess1, ChunkStatus.FULL);
- if (ichunkaccess1 instanceof Chunk) {
- return (Chunk) ichunkaccess1;
- }
- }
-
- return null;
- }
- }
+ return this.getChunkAtIfLoadedMainThread(i, j); // Paper - optimise for loaded chunks
}
}