Paper/patches/server/0491-Improve-Chunk-Status-Transition-Speed.patch
Josh Roy bc0dd0df3d Updated Upstream (Bukkit/CraftBukkit/Spigot)
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:
716b4fce Revert SnakeYAML upgrade
ca6f8942 Update to Minecraft 1.18-rc3
57e7e952 #683: Add Player#showDemoScreen

CraftBukkit Changes:
c98abfb0 Update to Minecraft 1.18-rc3
9b258501 #960: Add Player#showDemoScreen
d9542247 Produce remapped jars after bootstrap jar
99f3ddde SPIGOT-6808: Fix RegionAccessor#getBiome

Spigot Changes:
b7a4222e Update to Minecraft 1.18-rc3
2021-11-30 19:26:33 +01:00

82 Zeilen
4.4 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Fri, 29 May 2020 23:32:14 -0400
Subject: [PATCH] Improve Chunk Status Transition Speed
When a chunk is loaded from disk that has already been generated,
the server has to promote the chunk through the system to reach
it's current desired status level.
This results in every single status transition going from the main thread
to the world gen threads, only to discover it has no work it actually
needs to do.... and then it returns back to main.
This back and forth costs a lot of time and can really delay chunk loads
when the server is under high TPS due to their being a lot of time in
between chunk load times, as well as hogs up the chunk threads from doing
actual generation and light work.
Additionally, the whole task system uses a lot of CPU on the server threads anyways.
So by optimizing status transitions for status's that are already complete,
we can run them to the desired level while on main thread (where it has
to happen anyways) instead of ever jumping to world gen thread.
This will improve chunk loading effeciency to be reduced down to the following
scenario / path:
1) MAIN: Chunk Requested, Load Request sent to ChunkTaskManager / IO Queue
2) IO: Once position in queue comes, submit read IO data and schedule to chunk task thread
3) CHUNK: Once IO is loaded and position in queue comes, deserialize the chunk data, process conversions, submit to main queue
4) MAIN: next Chunk Task process (Mid Tick or End Of Tick), load chunk data into world (POI, main thread tasks)
5) MAIN: process status transitions all the way to LIGHT, light schedules Threaded task
6) SERVER: Light tasks register light enablement for chunk and any lighting needing to be done
7) MAIN: Task returns to main, finish processing to FULL/TICKING status
Previously would have hopped to SERVER around 12+ times there extra.
diff --git a/src/main/java/net/minecraft/server/level/ChunkHolder.java b/src/main/java/net/minecraft/server/level/ChunkHolder.java
index 26cafbffd6820411df6b9c41bd295883e1090c40..5b9abfb7b8edd686f416a46851f12bd52bea7000 100644
--- a/src/main/java/net/minecraft/server/level/ChunkHolder.java
+++ b/src/main/java/net/minecraft/server/level/ChunkHolder.java
@@ -87,6 +87,13 @@ public class ChunkHolder {
// Paper end - optimise isOutsideOfRange
long lastAutoSaveTime; // Paper - incremental autosave
long inactiveTimeStart; // Paper - incremental autosave
+ // Paper start - optimize chunk status progression without jumping through thread pool
+ public boolean canAdvanceStatus() {
+ ChunkStatus status = getChunkHolderStatus();
+ ChunkAccess chunk = getAvailableChunkNow();
+ return chunk != null && (status == null || chunk.getStatus().isOrAfter(getNextStatus(status)));
+ }
+ // Paper end
public ChunkHolder(ChunkPos pos, int level, LevelHeightAccessor world, LevelLightEngine lightingProvider, ChunkHolder.LevelChangeListener levelUpdateListener, ChunkHolder.PlayerProvider playersWatchingChunkProvider) {
this.futures = new AtomicReferenceArray(ChunkHolder.CHUNK_STATUSES.size());
diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java
index 4c48dcdb825e041a1d7392cea0e8afb687d45a0a..d9f6d47629f2f4aa1db5a19b8cb7229a0905b75e 100644
--- a/src/main/java/net/minecraft/server/level/ChunkMap.java
+++ b/src/main/java/net/minecraft/server/level/ChunkMap.java
@@ -674,7 +674,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
return either.mapLeft((list) -> {
return (LevelChunk) list.get(list.size() / 2);
});
- }, this.mainThreadExecutor);
+ }, this.mainInvokingExecutor); // Paper
}
@Nullable
@@ -1084,6 +1084,12 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider
return "chunkGenerate " + requiredStatus.getName();
});
Executor executor = (runnable) -> {
+ // Paper start - optimize chunk status progression without jumping through thread pool
+ if (holder.canAdvanceStatus()) {
+ this.mainInvokingExecutor.execute(runnable);
+ return;
+ }
+ // Paper end
this.worldgenMailbox.tell(ChunkTaskPriorityQueueSorter.message(holder, runnable));
};