PaperMC/Spigot-Server-Patches/0061-Chunk-save-queue-improvements.patch
Shane Freeder b9badbf2bc
Updated Upstream (Bukkit/CraftBukkit/Spigot)
Upstream has released updates that appears 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:
79f6ba25 Skip tests on default builds
b85cc32f Further discourage World.regenerateChunk

CraftBukkit Changes:
7560d3b5 Skip tests on default builds
d0a9130d SPIGOT-4563: Fix regenerating chunks saved to disk already

Spigot Changes:
8173d06f Remove need for redundant second clone of repositories
8ede0393 Rebuild patches
2019-01-04 19:19:36 +00:00

206 lines
10 KiB
Diff

From 2eb12d8fcb6b1715e3583e9b3333f5032a7b240d Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Fri, 4 Mar 2016 18:18:37 -0600
Subject: [PATCH] Chunk save queue improvements
For some unknown reason, Minecraft is sleeping 10ms between every single chunk being saved to disk.
Under high chunk load/unload activity (lots of movement / teleporting), this causes the chunk unload queue
to build up in size.
This has multiple impacts:
1) Performance of the unload queue itself - The save thread is pretty ineffecient for how it accesses it
By letting the queue get larger, checking and popping work off the queue can get less performant.
2) Performance of chunk loading - As with #1, chunk loads also have to check this queue when loading
chunk data so that it doesn't load stale data if new data is pending write to disk.
3) Memory Usage - The entire chunk has been serialized to NBT, and now sits in this queue. This leads to
elevated memory usage, and then the objects used in the serialization sit around longer than needed,
resulting in promotion to Old Generation instead of dying young.
To optimize this, we change the entire unload queue to be a proper queue. This improves the behavior of popping
the first queued chunk off, instead of abusing iterators like Mojang was doing.
This also improves reliability of chunk saving, as the previous hack job had a race condition that could
fail to save some chunks.
Then finally, Sleeping will by default be removed, but due to known issues with 1.9, a config option was added.
But if sleeps are to remain enabled, we at least lower the sleep interval so it doesn't have as much negative impact.
diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
index cc69ff3a4..f80b385ff 100644
--- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
@@ -217,4 +217,10 @@ public class PaperConfig {
" - Interval: " + timeSummary(Timings.getHistoryInterval() / 20) +
" - Length: " + timeSummary(Timings.getHistoryLength() / 20));
}
+
+ public static boolean enableFileIOThreadSleep;
+ private static void enableFileIOThreadSleep() {
+ enableFileIOThreadSleep = getBoolean("settings.sleep-between-chunk-saves", false);
+ if (enableFileIOThreadSleep) Bukkit.getLogger().info("Enabled sleeping between chunk saves, beware of memory issues");
+ }
}
diff --git a/src/main/java/net/minecraft/server/ChunkCoordIntPair.java b/src/main/java/net/minecraft/server/ChunkCoordIntPair.java
index b0c004b1f..d2cece265 100644
--- a/src/main/java/net/minecraft/server/ChunkCoordIntPair.java
+++ b/src/main/java/net/minecraft/server/ChunkCoordIntPair.java
@@ -20,6 +20,7 @@ public class ChunkCoordIntPair {
this.z = (int) (i >> 32);
}
+ public long asLong() { return a(); } // Paper
public long a() {
return a(this.x, this.z);
}
diff --git a/src/main/java/net/minecraft/server/ChunkRegionLoader.java b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
index 35976a26f..21ee154a5 100644
--- a/src/main/java/net/minecraft/server/ChunkRegionLoader.java
+++ b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
@@ -20,6 +20,7 @@ import java.util.Map.Entry;
import java.util.function.Consumer;
import java.util.function.Function;
import javax.annotation.Nullable;
+import java.util.concurrent.ConcurrentLinkedQueue; // Paper
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
// Spigot start
@@ -29,8 +30,28 @@ import org.spigotmc.SupplierUtils;
public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
+ // Paper start - Chunk queue improvements
+ private static class QueuedChunk {
+ public ChunkCoordIntPair coords;
+ public Supplier<NBTTagCompound> compoundSupplier;
+ public Runnable onSave;
+
+ public QueuedChunk(Runnable run) {
+ this.coords = null;
+ this.compoundSupplier = null;
+ this.onSave = run;
+ }
+
+ public QueuedChunk(ChunkCoordIntPair coords, Supplier<NBTTagCompound> compoundSupplier) {
+ this.coords = coords;
+ this.compoundSupplier = compoundSupplier;
+ }
+ }
+ final private ConcurrentLinkedQueue<QueuedChunk> queue = new ConcurrentLinkedQueue<>();
+ // Paper end
+
private static final Logger a = LogManager.getLogger();
- private final Map<ChunkCoordIntPair, Supplier<NBTTagCompound>> b = Maps.newHashMap();
+ private final it.unimi.dsi.fastutil.longs.Long2ObjectMap<Supplier<NBTTagCompound>> saveMap = it.unimi.dsi.fastutil.longs.Long2ObjectMaps.synchronize(new it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap<>()); // Paper
private final File c;
private final DataFixer d;
private PersistentStructureLegacy e;
@@ -86,7 +107,7 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
return null;
}
// CraftBukkit end
- NBTTagCompound nbttagcompound = SupplierUtils.getIfExists(this.b.get(new ChunkCoordIntPair(i, j))); // Spigot
+ NBTTagCompound nbttagcompound = SupplierUtils.getIfExists(this.saveMap.get(ChunkCoordIntPair.asLong(i, j))); // Spigot // Paper
if (nbttagcompound != null) {
return nbttagcompound;
@@ -314,7 +335,7 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
};
}
- this.a(chunkcoordintpair, SupplierUtils.createUnivaluedSupplier(completion, unloaded && this.b.size() < SAVE_QUEUE_TARGET_SIZE));
+ this.a(chunkcoordintpair, SupplierUtils.createUnivaluedSupplier(completion, unloaded)); // Paper - Remove save queue target size
// Spigot end
} catch (Exception exception) {
ChunkRegionLoader.a.error("Failed to save chunk", exception);
@@ -323,7 +344,8 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
}
protected void a(ChunkCoordIntPair chunkcoordintpair, Supplier<NBTTagCompound> nbttagcompound) { // Spigot
- this.b.put(chunkcoordintpair, nbttagcompound);
+ this.saveMap.put(chunkcoordintpair.asLong(), nbttagcompound); // Paper
+ queue.add(new QueuedChunk(chunkcoordintpair, nbttagcompound)); // Paper - Chunk queue improvements
FileIOThread.a().a(this);
}
@@ -333,20 +355,24 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
}
private boolean processSaveQueueEntry(boolean logCompletion) {
- Iterator<Entry<ChunkCoordIntPair, Supplier<NBTTagCompound>>> iterator = this.b.entrySet().iterator(); // Spigot
-
- if (!iterator.hasNext()) {
+ // Paper start - Chunk queue improvements
+ QueuedChunk chunk = queue.poll();
+ if (chunk == null) {
+ // Paper - end
if (logCompletion) { // CraftBukkit
ChunkRegionLoader.a.info("ThreadedAnvilChunkStorage ({}): All chunks are saved", this.c.getName());
}
return false;
} else {
- Entry<ChunkCoordIntPair, NBTTagCompound> entry = (Entry) iterator.next();
-
- iterator.remove();
- ChunkCoordIntPair chunkcoordintpair = (ChunkCoordIntPair) entry.getKey();
- Supplier<NBTTagCompound> nbttagcompound = (Supplier<NBTTagCompound>) entry.getValue(); // Spigot
+ // Paper start
+ if (chunk.onSave != null) {
+ chunk.onSave.run();
+ return true;
+ }
+ // Paper end
+ ChunkCoordIntPair chunkcoordintpair = chunk.coords; // Paper - Chunk queue improvements
+ Supplier<NBTTagCompound> nbttagcompound = chunk.compoundSupplier; // Spigot // Paper
if (nbttagcompound == null) {
return true;
@@ -355,6 +381,15 @@ public class ChunkRegionLoader implements IChunkLoader, IAsyncChunkSaver {
// CraftBukkit start
RegionFileCache.write(this.c, chunkcoordintpair.x, chunkcoordintpair.z, SupplierUtils.getIfExists(nbttagcompound)); // Spigot
+ // Paper start remove from map only if this was the latest version of the chunk
+ synchronized (this.saveMap) {
+ long k = chunkcoordintpair.asLong();
+ // This will not equal if a newer version is still pending - wait until newest is saved to remove
+ if (this.saveMap.get(k) == chunk.compoundSupplier) {
+ this.saveMap.remove(k);
+ }
+ }
+ // Paper end
/*
NBTCompressedStreamTools.a(nbttagcompound, (DataOutput) dataoutputstream);
dataoutputstream.close();
diff --git a/src/main/java/net/minecraft/server/FileIOThread.java b/src/main/java/net/minecraft/server/FileIOThread.java
index 8c3537ab8..3c688f546 100644
--- a/src/main/java/net/minecraft/server/FileIOThread.java
+++ b/src/main/java/net/minecraft/server/FileIOThread.java
@@ -38,20 +38,21 @@ public class FileIOThread implements Runnable {
IAsyncChunkSaver iasyncchunksaver = (IAsyncChunkSaver) this.c.get(i);
boolean flag;
- synchronized (iasyncchunksaver) {
+ //synchronized (iasyncchunksaver) { // Paper - remove synchronized
flag = iasyncchunksaver.a();
- }
+ //} // Paper
if (!flag) {
this.c.remove(i--);
++this.e;
}
+ if (com.destroystokyo.paper.PaperConfig.enableFileIOThreadSleep) { // Paper
try {
- Thread.sleep(this.f ? 0L : 10L);
+ Thread.sleep(this.f ? 0L : 1L); // Paper
} catch (InterruptedException interruptedexception) {
interruptedexception.printStackTrace();
- }
+ }} // Paper
}
if (this.c.isEmpty()) {
--
2.20.1