PaperMC/Spigot-Server-Patches/Optimize-NibbleArray-to-use-pooled-buffers.patch
Aikar 09a640626a Fix high memory use of non ticking chunks
The nibble pooling for NBT Tags was 'semi' leaked from loaded chunks
as we store the NBT Tag of Tile Entities in a Chunk, but don't process
them and remove them until chunk reaches Entity Ticking status....

This caused some phantom references to persist causing high memory use
of these chunks.

So I just got rid of pooling from NBT deserialization and we'll have to
take the hit on memory allocations there because too many cascading concerns
with anyone using NBT Tag Byte Arrays.

Fixes #3431
2020-05-22 18:58:26 -04:00

357 lines
16 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 6 May 2020 23:30:30 -0400
Subject: [PATCH] Optimize NibbleArray to use pooled buffers
Massively reduces memory allocation of 2048 byte buffers by using
an object pool for these.
Uses lots of advanced new capabilities of the Paper codebase :)
diff --git a/src/main/java/net/minecraft/server/ChunkRegionLoader.java b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/ChunkRegionLoader.java
+++ b/src/main/java/net/minecraft/server/ChunkRegionLoader.java
@@ -0,0 +0,0 @@ public class ChunkRegionLoader {
}
if (nibblearray != null && !nibblearray.c()) {
- nbttagcompound2.setByteArray("BlockLight", nibblearray.asBytes());
+ nbttagcompound2.setByteArray("BlockLight", nibblearray.asBytesPoolSafe().clone()); // Paper
}
if (nibblearray1 != null && !nibblearray1.c()) {
- nbttagcompound2.setByteArray("SkyLight", nibblearray1.asBytes());
+ nbttagcompound2.setByteArray("SkyLight", nibblearray1.asBytesPoolSafe().clone()); // Paper
}
nbttaglist.add(nbttagcompound2);
diff --git a/src/main/java/net/minecraft/server/LightEngineStorage.java b/src/main/java/net/minecraft/server/LightEngineStorage.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/LightEngineStorage.java
+++ b/src/main/java/net/minecraft/server/LightEngineStorage.java
@@ -0,0 +0,0 @@ public abstract class LightEngineStorage<M extends LightEngineStorageArray<M>> e
protected NibbleArray j(long i) {
NibbleArray nibblearray = (NibbleArray) this.i.get(i);
- return nibblearray != null ? nibblearray : new NibbleArray();
+ return nibblearray != null ? nibblearray : new NibbleArray().markPoolSafe(); // Paper
}
protected void a(LightEngineLayer<?, ?> lightenginelayer, long i) {
@@ -0,0 +0,0 @@ public abstract class LightEngineStorage<M extends LightEngineStorageArray<M>> e
if (nibblearray != null) {
this.i.put(i, nibblearray);
} else {
- this.i.remove(i);
+ NibbleArray remove = this.i.remove(i); if (remove != null && remove.cleaner != null) remove.cleaner.run(); // Paper - clean up when removed
}
}
diff --git a/src/main/java/net/minecraft/server/LightEngineStorageArray.java b/src/main/java/net/minecraft/server/LightEngineStorageArray.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/LightEngineStorageArray.java
+++ b/src/main/java/net/minecraft/server/LightEngineStorageArray.java
@@ -0,0 +0,0 @@ public abstract class LightEngineStorageArray<M extends LightEngineStorageArray<
public void a(long i) {
if (this.isVisible) { throw new IllegalStateException("writing to visible data"); } // Paper - avoid copying light data
- this.data.queueUpdate(i, ((NibbleArray) this.data.getUpdating(i)).b()); // Paper - avoid copying light data
+ this.data.queueUpdate(i, new NibbleArray().markPoolSafe(this.data.getUpdating(i).getCloneIfSet())); // Paper - avoid copying light data - pool safe clone
this.c();
}
diff --git a/src/main/java/net/minecraft/server/LightEngineStorageSky.java b/src/main/java/net/minecraft/server/LightEngineStorageSky.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/LightEngineStorageSky.java
+++ b/src/main/java/net/minecraft/server/LightEngineStorageSky.java
@@ -0,0 +0,0 @@ public class LightEngineStorageSky extends LightEngineStorage<LightEngineStorage
j = SectionPosition.a(j, EnumDirection.UP);
}
- return new NibbleArray((new NibbleArrayFlat(nibblearray1, 0)).asBytes());
+ return new NibbleArray().markPoolSafe(new NibbleArrayFlat(nibblearray1, 0).asBytes()); // Paper - mark pool use as safe (no auto cleaner)
} else {
- return new NibbleArray();
+ return new NibbleArray().markPoolSafe(); // Paper - mark pool use as safe (no auto cleaner)
}
}
}
@@ -0,0 +0,0 @@ public class LightEngineStorageSky extends LightEngineStorage<LightEngineStorage
((LightEngineStorageSky.a) this.f).a(i);
}
- Arrays.fill(this.a(i, true).asBytes(), (byte) -1);
+ Arrays.fill(this.a(i, true).asBytesPoolSafe(), (byte) -1); // Paper
k = SectionPosition.c(SectionPosition.b(i));
l = SectionPosition.c(SectionPosition.c(i));
int i1 = SectionPosition.c(SectionPosition.d(i));
diff --git a/src/main/java/net/minecraft/server/NibbleArray.java b/src/main/java/net/minecraft/server/NibbleArray.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/NibbleArray.java
+++ b/src/main/java/net/minecraft/server/NibbleArray.java
@@ -0,0 +0,0 @@
package net.minecraft.server;
+import com.destroystokyo.paper.util.pooled.PooledObjects; // Paper
+
+import javax.annotation.Nonnull;
import javax.annotation.Nullable;
public class NibbleArray {
- @Nullable
- protected byte[] a;
+ // Paper start
+ public static byte[] EMPTY_NIBBLE = new byte[2048];
+ private static final int nibbleBucketSizeMultiplier = Integer.getInteger("Paper.nibbleBucketSize", 3072);
+ private static final int maxPoolSize = Integer.getInteger("Paper.maxNibblePoolSize", (int) Math.min(6, Math.max(1, Runtime.getRuntime().maxMemory() / 1024 / 1024 / 1024)) * (nibbleBucketSizeMultiplier * 8));
+ public static final PooledObjects<byte[]> BYTE_2048 = new PooledObjects<>(() -> new byte[2048], maxPoolSize);
+ public static void releaseBytes(byte[] bytes) {
+ if (bytes != null && bytes != EMPTY_NIBBLE && bytes.length == 2048) {
+ System.arraycopy(EMPTY_NIBBLE, 0, bytes, 0, 2048);
+ BYTE_2048.release(bytes);
+ }
+ }
+
+ public NibbleArray markPoolSafe(byte[] bytes) {
+ if (bytes != EMPTY_NIBBLE) this.a = bytes;
+ return markPoolSafe();
+ }
+ public NibbleArray markPoolSafe() {
+ poolSafe = true;
+ return this;
+ }
+ public byte[] getIfSet() {
+ return this.a != null ? this.a : EMPTY_NIBBLE;
+ }
+ public byte[] getCloneIfSet() {
+ if (a == null) {
+ return EMPTY_NIBBLE;
+ }
+ byte[] ret = BYTE_2048.acquire();
+ System.arraycopy(getIfSet(), 0, ret, 0, 2048);
+ return ret;
+ }
+
+ public NibbleArray cloneAndSet(byte[] bytes) {
+ if (bytes != null && bytes != EMPTY_NIBBLE) {
+ this.a = BYTE_2048.acquire();
+ System.arraycopy(bytes, 0, this.a, 0, 2048);
+ }
+ return this;
+ }
+ boolean poolSafe = false;
+ public java.lang.Runnable cleaner;
+ private void registerCleaner() {
+ if (!poolSafe) {
+ cleaner = MCUtil.registerCleaner(this, this.a, NibbleArray::releaseBytes);
+ } else {
+ cleaner = MCUtil.once(() -> NibbleArray.releaseBytes(this.a));
+ }
+ }
+ // Paper end
+ @Nullable protected byte[] a;
+
public NibbleArray() {}
public NibbleArray(byte[] abyte) {
+ // Paper start
+ this(abyte, false);
+ }
+ public NibbleArray(byte[] abyte, boolean isSafe) {
this.a = abyte;
+ if (!isSafe) this.a = getCloneIfSet(); // Paper - clone for safety
+ registerCleaner();
+ // Paper end
if (abyte.length != 2048) {
throw (IllegalArgumentException) SystemUtils.c(new IllegalArgumentException("ChunkNibbleArrays should be 2048 bytes not: " + abyte.length));
}
@@ -0,0 +0,0 @@ public class NibbleArray {
public void a(int i, int j) { // PAIL: private -> public
if (this.a == null) {
- this.a = new byte[2048];
+ this.a = BYTE_2048.acquire(); // Paper
+ registerCleaner();// Paper
}
int k = this.d(i);
@@ -0,0 +0,0 @@ public class NibbleArray {
public byte[] asBytes() {
if (this.a == null) {
this.a = new byte[2048];
+ } else { // Paper start
+ // Accessor may need this object past garbage collection so need to clone it and return pooled value
+ // If we know its safe for pre GC access, use asBytesPoolSafe(). If you just need read, use getIfSet()
+ Runnable cleaner = this.cleaner;
+ if (cleaner != null) {
+ this.a = this.a.clone();
+ cleaner.run(); // release the previously pooled value
+ this.cleaner = null;
+ }
+ }
+ // Paper end
+
+ return this.a;
+ }
+
+ @Nonnull
+ public byte[] asBytesPoolSafe() {
+ if (this.a == null) {
+ this.a = BYTE_2048.acquire(); // Paper
+ registerCleaner(); // Paper
}
+ //noinspection ConstantConditions
return this.a;
}
+ // Paper end
public NibbleArray copy() { return this.b(); } // Paper - OBFHELPER
public NibbleArray b() {
- return this.a == null ? new NibbleArray() : new NibbleArray((byte[]) this.a.clone());
+ return this.a == null ? new NibbleArray() : new NibbleArray(this.a); // Paper - clone in ctor
}
public String toString() {
diff --git a/src/main/java/net/minecraft/server/NibbleArrayFlat.java b/src/main/java/net/minecraft/server/NibbleArrayFlat.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/NibbleArrayFlat.java
+++ b/src/main/java/net/minecraft/server/NibbleArrayFlat.java
@@ -0,0 +0,0 @@ public class NibbleArrayFlat extends NibbleArray {
public NibbleArrayFlat(NibbleArray nibblearray, int i) {
super(128);
- System.arraycopy(nibblearray.asBytes(), i * 128, this.a, 0, 128);
+ System.arraycopy(nibblearray.getIfSet(), i * 128, this.a, 0, 128); // Paper
}
@Override
@@ -0,0 +0,0 @@ public class NibbleArrayFlat extends NibbleArray {
@Override
public byte[] asBytes() {
- byte[] abyte = new byte[2048];
+ byte[] abyte = BYTE_2048.acquire(); // Paper
for (int i = 0; i < 16; ++i) {
System.arraycopy(this.a, 0, abyte, i * 128, 128);
diff --git a/src/main/java/net/minecraft/server/PacketPlayOutLightUpdate.java b/src/main/java/net/minecraft/server/PacketPlayOutLightUpdate.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/PacketPlayOutLightUpdate.java
+++ b/src/main/java/net/minecraft/server/PacketPlayOutLightUpdate.java
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
private List<byte[]> g;
private List<byte[]> h;
+ // Paper start
+ java.lang.Runnable cleaner1;
+ java.lang.Runnable cleaner2;
+ java.util.concurrent.atomic.AtomicInteger remainingSends = new java.util.concurrent.atomic.AtomicInteger(0);
+
+ @Override
+ public void onPacketDispatch(EntityPlayer player) {
+ remainingSends.incrementAndGet();
+ }
+
+ @Override
+ public void onPacketDispatchFinish(EntityPlayer player, io.netty.channel.ChannelFuture future) {
+ if (remainingSends.decrementAndGet() <= 0) {
+ // incase of any race conditions, schedule this delayed
+ MCUtil.scheduleTask(1, () -> {
+ if (remainingSends.get() == 0) {
+ cleaner1.run();
+ cleaner2.run();
+ }
+ });
+ }
+ }
+
+ @Override
+ public boolean hasFinishListener() {
+ return true;
+ }
+
+ // Paper end
public PacketPlayOutLightUpdate() {}
public PacketPlayOutLightUpdate(ChunkCoordIntPair chunkcoordintpair, LightEngine lightengine) {
this.a = chunkcoordintpair.x;
this.b = chunkcoordintpair.z;
- this.g = Lists.newArrayList();
- this.h = Lists.newArrayList();
+ this.g = Lists.newArrayList();cleaner1 = MCUtil.registerListCleaner(this, this.g, NibbleArray::releaseBytes); // Paper
+ this.h = Lists.newArrayList();cleaner2 = MCUtil.registerListCleaner(this, this.h, NibbleArray::releaseBytes); // Paper
for (int i = 0; i < 18; ++i) {
NibbleArray nibblearray = lightengine.a(EnumSkyBlock.SKY).a(SectionPosition.a(chunkcoordintpair, -1 + i));
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
this.e |= 1 << i;
} else {
this.c |= 1 << i;
- this.g.add(nibblearray.asBytes().clone());
+ this.g.add(nibblearray.getCloneIfSet()); // Paper
}
}
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
this.f |= 1 << i;
} else {
this.d |= 1 << i;
- this.h.add(nibblearray1.asBytes().clone());
+ this.h.add(nibblearray1.getCloneIfSet()); // Paper
}
}
}
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
this.b = chunkcoordintpair.z;
this.c = i;
this.d = j;
- this.g = Lists.newArrayList();
- this.h = Lists.newArrayList();
+ this.g = Lists.newArrayList();cleaner1 = MCUtil.registerListCleaner(this, this.g, NibbleArray::releaseBytes); // Paper
+ this.h = Lists.newArrayList();cleaner2 = MCUtil.registerListCleaner(this, this.h, NibbleArray::releaseBytes); // Paper
for (int k = 0; k < 18; ++k) {
NibbleArray nibblearray;
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
if ((this.c & 1 << k) != 0) {
nibblearray = lightengine.a(EnumSkyBlock.SKY).a(SectionPosition.a(chunkcoordintpair, -1 + k));
if (nibblearray != null && !nibblearray.c()) {
- this.g.add(nibblearray.asBytes().clone());
+ this.g.add(nibblearray.getCloneIfSet()); // Paper
} else {
this.c &= ~(1 << k);
if (nibblearray != null) {
@@ -0,0 +0,0 @@ public class PacketPlayOutLightUpdate implements Packet<PacketListenerPlayOut> {
if ((this.d & 1 << k) != 0) {
nibblearray = lightengine.a(EnumSkyBlock.BLOCK).a(SectionPosition.a(chunkcoordintpair, -1 + k));
if (nibblearray != null && !nibblearray.c()) {
- this.h.add(nibblearray.asBytes().clone());
+ this.h.add(nibblearray.getCloneIfSet()); // Paper
} else {
this.d &= ~(1 << k);
if (nibblearray != null) {
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftChunk.java b/src/main/java/org/bukkit/craftbukkit/CraftChunk.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftChunk.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftChunk.java
@@ -0,0 +0,0 @@ public class CraftChunk implements Chunk {
sectionSkyLights[i] = emptyLight;
} else {
sectionSkyLights[i] = new byte[2048];
- System.arraycopy(skyLightArray.asBytes(), 0, sectionSkyLights[i], 0, 2048);
+ System.arraycopy(skyLightArray.getIfSet(), 0, sectionSkyLights[i], 0, 2048); // Paper
}
NibbleArray emitLightArray = lightengine.a(EnumSkyBlock.BLOCK).a(SectionPosition.a(x, i, z));
if (emitLightArray == null) {
sectionEmitLights[i] = emptyLight;
} else {
sectionEmitLights[i] = new byte[2048];
- System.arraycopy(emitLightArray.asBytes(), 0, sectionEmitLights[i], 0, 2048);
+ System.arraycopy(emitLightArray.getIfSet(), 0, sectionEmitLights[i], 0, 2048); // Paper
}
}
}