Paper/Spigot-Server-Patches/0429-Mid-Tick-Chunk-Tasks-Speed-up-processing-of-chunk-lo.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

264 lines
13 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 9 Apr 2020 00:09:26 -0400
Subject: [PATCH] Mid Tick Chunk Tasks - Speed up processing of chunk loads and
generation
Credit to Spotted for the idea
A lot of the new chunk system requires constant back and forth the main thread
to handle priority scheduling and ensuring conflicting tasks do not run at the
same time.
The issue is, these queues are only checked at either:
A) Sync Chunk Loads
B) End of Tick while sleeping
This results in generating chunks sitting waiting for a full tick to
complete before it will even start the next unit of work to do.
Additionally, this also delays loading of chunks until this same timing.
We will now periodically poll the chunk task queues throughout the tick,
looking for work to do.
We do this in a fair method that considers all worlds, not just the one being
ticked, so that each world can get 1 task procesed each before the next pass.
In a view distance of 15, chunk loading performance was visually faster on the client.
Flying at high speed in spectator mode was able to keep up with chunk loading (as long as they are already generated)
diff --git a/src/main/java/co/aikar/timings/MinecraftTimings.java b/src/main/java/co/aikar/timings/MinecraftTimings.java
index 11fe3524f38f7756ebd0e3807678e8848fd2217d..884b59d478aa7de49906520e77866a7949bed19d 100644
--- a/src/main/java/co/aikar/timings/MinecraftTimings.java
+++ b/src/main/java/co/aikar/timings/MinecraftTimings.java
@@ -13,6 +13,7 @@ import java.util.Map;
public final class MinecraftTimings {
public static final Timing serverOversleep = Timings.ofSafe("Server Oversleep");
+ public static final Timing midTickChunkTasks = Timings.ofSafe("Mid Tick Chunk Tasks");
public static final Timing playerListTimer = Timings.ofSafe("Player List");
public static final Timing commandFunctionsTimer = Timings.ofSafe("Command Functions");
public static final Timing connectionTimer = Timings.ofSafe("Connection Handler");
diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
index 519b43154993ec01eb13a58336ddcc745362892f..63b3726bfdd22900e7bc577c34db58ddba1084ee 100644
--- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
@@ -405,4 +405,9 @@ public class PaperConfig {
log("Async Chunks: Enabled - Chunks will be loaded much faster, without lag.");
}
}
+
+ public static int midTickChunkTasks = 1000;
+ private static void midTickChunkTasks() {
+ midTickChunkTasks = getInt("settings.chunk-tasks-per-tick", midTickChunkTasks);
+ }
}
diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index 44aa6baed64a0d3847cd8df067e0fa32a0739c93..cc7691a2ed5eaa30071ad5e385bbd76bec3c3d80 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -686,6 +686,7 @@ public class ChunkProviderServer extends IChunkProvider {
this.world.getMethodProfiler().enter("purge");
this.world.timings.doChunkMap.startTiming(); // Spigot
this.chunkMapDistance.purgeTickets();
+ this.world.getMinecraftServer().midTickLoadChunks(); // Paper
this.tickDistanceManager();
this.world.timings.doChunkMap.stopTiming(); // Spigot
this.world.getMethodProfiler().exitEnter("chunks");
@@ -695,6 +696,7 @@ public class ChunkProviderServer extends IChunkProvider {
this.world.timings.doChunkUnload.startTiming(); // Spigot
this.world.getMethodProfiler().exitEnter("unload");
this.playerChunkMap.unloadChunks(booleansupplier);
+ this.world.getMinecraftServer().midTickLoadChunks(); // Paper
this.world.timings.doChunkUnload.stopTiming(); // Spigot
this.world.getMethodProfiler().exit();
this.clearCache();
@@ -748,7 +750,7 @@ public class ChunkProviderServer extends IChunkProvider {
entityPlayer.playerNaturallySpawnedEvent.callEvent();
};
// Paper end
- this.playerChunkMap.forEachVisibleChunk((playerchunk) -> { // Paper - safe iterator incase chunk loads, also no wrapping
+ final int[] chunksTicked = {0}; this.playerChunkMap.forEachVisibleChunk((playerchunk) -> { // Paper - safe iterator incase chunk loads, also no wrapping
Optional<Chunk> optional = ((Either) playerchunk.a().getNow(PlayerChunk.UNLOADED_CHUNK)).left();
if (optional.isPresent()) {
@@ -772,6 +774,7 @@ public class ChunkProviderServer extends IChunkProvider {
this.world.timings.chunkTicks.startTiming(); // Spigot // Paper
this.world.a(chunk, k);
this.world.timings.chunkTicks.stopTiming(); // Spigot // Paper
+ if (chunksTicked[0]++ % 10 == 0) this.world.getMinecraftServer().midTickLoadChunks(); // Paper
}
}
}
@@ -928,6 +931,41 @@ public class ChunkProviderServer extends IChunkProvider {
super.executeTask(runnable);
}
+ // Paper start
+ private long lastMidTickChunkTask = 0;
+ public boolean pollChunkLoadTasks() {
+ if (com.destroystokyo.paper.io.chunk.ChunkTaskManager.pollChunkWaitQueue() || ChunkProviderServer.this.world.asyncChunkTaskManager.pollNextChunkTask()) {
+ try {
+ ChunkProviderServer.this.tickDistanceManager();
+ } finally {
+ // from below: process pending Chunk loadCallback() and unloadCallback() after each run task
+ playerChunkMap.callbackExecutor.run();
+ }
+ return true;
+ }
+ return false;
+ }
+ public void midTickLoadChunks() {
+ MinecraftServer server = ChunkProviderServer.this.world.getMinecraftServer();
+ // always try to load chunks, restrain generation/other updates only. don't count these towards tick count
+ //noinspection StatementWithEmptyBody
+ while (pollChunkLoadTasks()) {}
+
+ if (System.nanoTime() - lastMidTickChunkTask < 200000) {
+ return;
+ }
+
+ for (;server.midTickChunksTasksRan < com.destroystokyo.paper.PaperConfig.midTickChunkTasks && server.canSleepForTick();) {
+ if (this.executeNext()) {
+ server.midTickChunksTasksRan++;
+ lastMidTickChunkTask = System.nanoTime();
+ } else {
+ break;
+ }
+ }
+ }
+ // Paper end
+
@Override
protected boolean executeNext() {
// CraftBukkit start - process pending Chunk loadCallback() and unloadCallback() after each run task
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 1647c36c2b8f81be59ed48eb329977331aa709b1..3149caeee2ad6e31806530b794f265315105ef5a 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -935,6 +935,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
// Paper end
tickSection = curTime;
}
+ midTickChunksTasksRan = 0; // Paper
// Spigot end
//MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit // Paper - don't overwrite current tick time
@@ -1004,7 +1005,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
}
- private boolean canSleepForTick() {
+ public boolean canSleepForTick() { // Paper
// CraftBukkit start
if (isOversleep) return canOversleep();// Paper - because of our changes, this logic is broken
return this.forceTicks || this.isEntered() || SystemUtils.getMonotonicMillis() < (this.X ? this.W : this.nextTick);
@@ -1034,6 +1035,23 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
});
}
+ // Paper start
+ public int midTickChunksTasksRan = 0;
+ private long midTickLastRan = 0;
+ public void midTickLoadChunks() {
+ if (!isMainThread() || System.nanoTime() - midTickLastRan < 1000000) {
+ // only check once per 0.25ms incase this code is called in a hot method
+ return;
+ }
+ try (co.aikar.timings.Timing ignored = co.aikar.timings.MinecraftTimings.midTickChunkTasks.startTiming()) {
+ for (WorldServer value : this.getWorlds()) {
+ value.getChunkProvider().serverThreadQueue.midTickLoadChunks();
+ }
+ midTickLastRan = System.nanoTime();
+ }
+ }
+ // Paper end
+
@Override
protected TickTask postToMainThread(Runnable runnable) {
return new TickTask(this.ticks, runnable);
@@ -1120,6 +1138,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
// Paper start - move oversleep into full server tick
isOversleep = true;MinecraftTimings.serverOversleep.startTiming();
this.awaitTasks(() -> {
+ midTickLoadChunks(); // will only do loads since we are still considered !canSleepForTick
return !this.canOversleep();
});
isOversleep = false;MinecraftTimings.serverOversleep.stopTiming();
@@ -1198,13 +1217,16 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
}
protected void b(BooleanSupplier booleansupplier) {
+ midTickLoadChunks(); // Paper
MinecraftTimings.bukkitSchedulerTimer.startTiming(); // Spigot // Paper
this.server.getScheduler().mainThreadHeartbeat(this.ticks); // CraftBukkit
MinecraftTimings.bukkitSchedulerTimer.stopTiming(); // Spigot // Paper
+ midTickLoadChunks(); // Paper
this.methodProfiler.enter("commandFunctions");
MinecraftTimings.commandFunctionsTimer.startTiming(); // Spigot // Paper
this.getFunctionData().tick();
MinecraftTimings.commandFunctionsTimer.stopTiming(); // Spigot // Paper
+ midTickLoadChunks(); // Paper
this.methodProfiler.exitEnter("levels");
Iterator iterator = this.getWorlds().iterator();
@@ -1215,7 +1237,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
processQueue.remove().run();
}
MinecraftTimings.processQueueTimer.stopTiming(); // Spigot
-
+ midTickLoadChunks(); // Paper
MinecraftTimings.timeUpdateTimer.startTiming(); // Spigot // Paper
// Send time updates to everyone, it will get the right time from the world the player is in.
// Paper start - optimize time updates
@@ -1257,9 +1279,11 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
this.methodProfiler.enter("tick");
try {
+ midTickLoadChunks(); // Paper
worldserver.timings.doTick.startTiming(); // Spigot
worldserver.doTick(booleansupplier);
worldserver.timings.doTick.stopTiming(); // Spigot
+ midTickLoadChunks(); // Paper
} catch (Throwable throwable) {
// Spigot Start
CrashReport crashreport;
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index ed13a1bc54cebebbafbf9a3822d2942fbc09249e..87c581fe9c4e12f2cdf93d864ccc7383f2933304 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -457,6 +457,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
}
timings.scheduledBlocks.stopTiming(); // Paper
+ this.getMinecraftServer().midTickLoadChunks(); // Paper
gameprofilerfiller.exitEnter("raid");
this.timings.raids.startTiming(); // Paper - timings
this.persistentRaid.a();
@@ -465,6 +466,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
timings.doSounds.startTiming(); // Spigot
this.ak();
timings.doSounds.stopTiming(); // Spigot
+ this.getMinecraftServer().midTickLoadChunks(); // Paper
this.ticking = false;
gameprofilerfiller.exitEnter("entities");
boolean flag3 = true || !this.players.isEmpty() || !this.getForceLoadedChunks().isEmpty(); // CraftBukkit - this prevents entity cleanup, other issues on servers with no players
@@ -531,6 +533,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
timings.entityTick.stopTiming(); // Spigot
this.tickingEntities = false;
+ this.getMinecraftServer().midTickLoadChunks(); // Paper
Entity entity2;
@@ -540,6 +543,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
}
timings.tickEntities.stopTiming(); // Spigot
+ this.getMinecraftServer().midTickLoadChunks(); // Paper
this.tickBlockEntities();
}