From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Aikar Date: Wed, 8 Apr 2020 03:06:30 -0400 Subject: [PATCH] Optimize PlayerChunkMap memory use for visibleChunks No longer clones visible chunks which is causing massive memory allocation issues, likely the source of Humongous Objects on large servers. Instead we just synchronize, clear and rebuild, reusing the same object buffers as before with only 2 small objects created (FastIterator/MapEntry) This should result in siginificant memory use reduction and improved GC behavior. diff --git a/src/main/java/com/destroystokyo/paper/util/map/Long2ObjectLinkedOpenHashMapFastCopy.java b/src/main/java/com/destroystokyo/paper/util/map/Long2ObjectLinkedOpenHashMapFastCopy.java new file mode 100644 index 0000000000000000000000000000000000000000..f6ff4d8132a95895680f5bc81f8f873e78f0bbdb --- /dev/null +++ b/src/main/java/com/destroystokyo/paper/util/map/Long2ObjectLinkedOpenHashMapFastCopy.java @@ -0,0 +1,39 @@ +package com.destroystokyo.paper.util.map; + +import it.unimi.dsi.fastutil.longs.Long2ObjectLinkedOpenHashMap; + +public class Long2ObjectLinkedOpenHashMapFastCopy extends Long2ObjectLinkedOpenHashMap { + + public void copyFrom(Long2ObjectLinkedOpenHashMapFastCopy map) { + if (key.length != map.key.length) { + key = null; + key = new long[map.key.length]; + } + if (value.length != map.value.length) { + value = null; + //noinspection unchecked + value = (V[]) new Object[map.value.length]; + } + if (link.length != map.link.length) { + link = null; + link = new long[map.link.length]; + } + System.arraycopy(map.key, 0, this.key, 0, map.key.length); + System.arraycopy(map.value, 0, this.value, 0, map.value.length); + System.arraycopy(map.link, 0, this.link, 0, map.link.length); + this.size = map.size; + this.mask = map.mask; + this.first = map.first; + this.last = map.last; + this.n = map.n; + this.maxFill = map.maxFill; + this.containsNullKey = map.containsNullKey; + } + + @Override + public Long2ObjectLinkedOpenHashMapFastCopy clone() { + Long2ObjectLinkedOpenHashMapFastCopy clone = (Long2ObjectLinkedOpenHashMapFastCopy) super.clone(); + clone.copyFrom(this); + return clone; + } +} diff --git a/src/main/java/net/minecraft/server/MCUtil.java b/src/main/java/net/minecraft/server/MCUtil.java index 4bc418f45c6f16a9a1c78b6688625268870a96ad..2d5b8e35d52b0dfd075af81a3a936d8a21053b31 100644 --- a/src/main/java/net/minecraft/server/MCUtil.java +++ b/src/main/java/net/minecraft/server/MCUtil.java @@ -614,7 +614,7 @@ public final class MCUtil { ServerLevel world = ((org.bukkit.craftbukkit.CraftWorld)bukkitWorld).getHandle(); ChunkMap chunkMap = world.getChunkSource().chunkMap; - Long2ObjectLinkedOpenHashMap visibleChunks = chunkMap.visibleChunkMap; + Long2ObjectLinkedOpenHashMap visibleChunks = chunkMap.getVisibleChunks(); DistanceManager chunkMapDistance = chunkMap.distanceManager; List allChunks = new ArrayList<>(visibleChunks.values()); List players = world.players; diff --git a/src/main/java/net/minecraft/server/level/ChunkMap.java b/src/main/java/net/minecraft/server/level/ChunkMap.java index 2b291296821dc6d6a8437bd977eeba517cdb5003..962028a58ee54b99be20905c1fd16cfe15c82175 100644 --- a/src/main/java/net/minecraft/server/level/ChunkMap.java +++ b/src/main/java/net/minecraft/server/level/ChunkMap.java @@ -112,9 +112,36 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider private static final int MIN_VIEW_DISTANCE = 3; public static final int MAX_VIEW_DISTANCE = 33; public static final int MAX_CHUNK_DISTANCE = 33 + ChunkStatus.maxDistance(); + // Paper start - faster copying + public final Long2ObjectLinkedOpenHashMap updatingChunkMap = new com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy<>(); // Paper - faster copying + public final Long2ObjectLinkedOpenHashMap visibleChunkMap = new ProtectedVisibleChunksMap(); // Paper - faster copying + + private class ProtectedVisibleChunksMap extends com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy { + @Override + public ChunkHolder put(long k, ChunkHolder playerChunk) { + throw new UnsupportedOperationException("Updating visible Chunks"); + } + + @Override + public ChunkHolder remove(long k) { + throw new UnsupportedOperationException("Removing visible Chunks"); + } + + @Override + public ChunkHolder get(long k) { + return ChunkMap.this.getVisibleChunkIfPresent(k); + } + + public ChunkHolder safeGet(long k) { + return super.get(k); + } + } + // Paper end + public final com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy pendingVisibleChunks = new com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy(); // Paper - this is used if the visible chunks is updated while iterating only + public transient com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy visibleChunksClone; // Paper - used for async access of visible chunks, clone and cache only when needed public static final int FORCED_TICKET_LEVEL = 31; - public final Long2ObjectLinkedOpenHashMap updatingChunkMap = new Long2ObjectLinkedOpenHashMap(); - public volatile Long2ObjectLinkedOpenHashMap visibleChunkMap; + // public final Long2ObjectLinkedOpenHashMap updatingChunkMap = new Long2ObjectLinkedOpenHashMap(); // Paper - moved up + // public volatile Long2ObjectLinkedOpenHashMap visibleChunkMap; // Paper - moved up private final Long2ObjectLinkedOpenHashMap pendingUnloads; public final LongSet entitiesInLevel; public final ServerLevel level; @@ -237,7 +264,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider public ChunkMap(ServerLevel world, LevelStorageSource.LevelStorageAccess session, DataFixer dataFixer, StructureManager structureManager, Executor executor, BlockableEventLoop mainThreadExecutor, LightChunkGetter chunkProvider, ChunkGenerator chunkGenerator, ChunkProgressListener worldGenerationProgressListener, ChunkStatusUpdateListener chunkStatusChangeListener, Supplier persistentStateManagerFactory, int viewDistance, boolean dsync) { super(new File(session.getDimensionPath(world.dimension()), "region"), dataFixer, dsync); - this.visibleChunkMap = this.updatingChunkMap.clone(); + //this.visibleChunks = this.updatingChunks.clone(); // Paper - no more cloning this.pendingUnloads = new Long2ObjectLinkedOpenHashMap(); this.entitiesInLevel = new LongOpenHashSet(); this.toDrop = new LongOpenHashSet(); @@ -378,9 +405,52 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider return (ChunkHolder) this.updatingChunkMap.get(pos); } + // Paper start - remove cloning of visible chunks unless accessed as a collection async + private static final boolean DEBUG_ASYNC_VISIBLE_CHUNKS = Boolean.getBoolean("paper.debug-async-visible-chunks"); + private boolean isIterating = false; + private boolean hasPendingVisibleUpdate = false; + public void forEachVisibleChunk(java.util.function.Consumer consumer) { + org.spigotmc.AsyncCatcher.catchOp("forEachVisibleChunk"); + boolean prev = isIterating; + isIterating = true; + try { + for (ChunkHolder value : this.visibleChunkMap.values()) { + consumer.accept(value); + } + } finally { + this.isIterating = prev; + if (!this.isIterating && this.hasPendingVisibleUpdate) { + ((ProtectedVisibleChunksMap)this.visibleChunkMap).copyFrom(this.pendingVisibleChunks); + this.pendingVisibleChunks.clear(); + this.hasPendingVisibleUpdate = false; + } + } + } + public Long2ObjectLinkedOpenHashMap getVisibleChunks() { + if (Thread.currentThread() == this.level.thread) { + return this.visibleChunkMap; + } else { + synchronized (this.visibleChunkMap) { + if (DEBUG_ASYNC_VISIBLE_CHUNKS) new Throwable("Async getVisibleChunks").printStackTrace(); + if (this.visibleChunksClone == null) { + this.visibleChunksClone = this.hasPendingVisibleUpdate ? this.pendingVisibleChunks.clone() : ((ProtectedVisibleChunksMap)this.visibleChunkMap).clone(); + } + return this.visibleChunksClone; + } + } + } + // Paper end + @Nullable public ChunkHolder getVisibleChunkIfPresent(long pos) { - return (ChunkHolder) this.visibleChunkMap.get(pos); + // Paper start - mt safe get + if (Thread.currentThread() != this.level.thread) { + synchronized (this.visibleChunkMap) { + return (ChunkHolder) (this.hasPendingVisibleUpdate ? this.pendingVisibleChunks.get(pos) : ((ProtectedVisibleChunksMap)this.visibleChunkMap).safeGet(pos)); + } + } + return (ChunkHolder) (this.hasPendingVisibleUpdate ? this.pendingVisibleChunks.get(pos) : ((ProtectedVisibleChunksMap)this.visibleChunkMap).safeGet(pos)); + // Paper end } protected IntSupplier getChunkQueueLevel(long pos) { @@ -537,8 +607,9 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider } protected void saveAllChunks(boolean flush) { + Long2ObjectLinkedOpenHashMap visibleChunks = this.getVisibleChunks(); // Paper remove clone of visible Chunks unless saving off main thread (watchdog kill) if (flush) { - List list = (List) this.visibleChunkMap.values().stream().filter(ChunkHolder::wasAccessibleSinceLastSave).peek(ChunkHolder::refreshAccessibility).collect(Collectors.toList()); + List list = (List) visibleChunks.values().stream().filter(ChunkHolder::wasAccessibleSinceLastSave).peek(ChunkHolder::refreshAccessibility).collect(Collectors.toList()); // Paper - remove cloning of visible chunks MutableBoolean mutableboolean = new MutableBoolean(); do { @@ -568,7 +639,7 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider this.level.asyncChunkTaskManager.flush(); // Paper - flush to preserve behavior compat with pre-async behaviour // this.i(); // Paper - nuke IOWorker } else { - this.visibleChunkMap.values().stream().filter(ChunkHolder::wasAccessibleSinceLastSave).forEach((playerchunk) -> { + visibleChunks.values().stream().filter(ChunkHolder::wasAccessibleSinceLastSave).forEach((playerchunk) -> { ChunkAccess ichunkaccess = (ChunkAccess) playerchunk.getChunkToSave().getNow(null); // CraftBukkit - decompile error if (ichunkaccess instanceof ImposterProtoChunk || ichunkaccess instanceof LevelChunk) { @@ -726,7 +797,20 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider if (!this.modified) { return false; } else { - this.visibleChunkMap = this.updatingChunkMap.clone(); + // Paper start - stop cloning visibleChunks + synchronized (this.visibleChunkMap) { + if (isIterating) { + hasPendingVisibleUpdate = true; + this.pendingVisibleChunks.copyFrom((com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy)this.updatingChunkMap); + } else { + hasPendingVisibleUpdate = false; + this.pendingVisibleChunks.clear(); + ((ProtectedVisibleChunksMap)this.visibleChunkMap).copyFrom((com.destroystokyo.paper.util.map.Long2ObjectLinkedOpenHashMapFastCopy)this.updatingChunkMap); + this.visibleChunksClone = null; + } + } + // Paper end + this.modified = false; return true; } @@ -1173,12 +1257,12 @@ public class ChunkMap extends ChunkStorage implements ChunkHolder.PlayerProvider } protected Iterable getChunks() { - return Iterables.unmodifiableIterable(this.visibleChunkMap.values()); + return Iterables.unmodifiableIterable(this.getVisibleChunks().values()); // Paper } void dumpChunks(Writer writer) throws IOException { CsvOutput csvwriter = CsvOutput.builder().addColumn("x").addColumn("z").addColumn("level").addColumn("in_memory").addColumn("status").addColumn("full_status").addColumn("accessible_ready").addColumn("ticking_ready").addColumn("entity_ticking_ready").addColumn("ticket").addColumn("spawning").addColumn("block_entity_count").build(writer); - ObjectBidirectionalIterator objectbidirectionaliterator = this.visibleChunkMap.long2ObjectEntrySet().iterator(); + ObjectBidirectionalIterator objectbidirectionaliterator = this.getVisibleChunks().long2ObjectEntrySet().iterator(); // Paper while (objectbidirectionaliterator.hasNext()) { Entry entry = (Entry) objectbidirectionaliterator.next(); diff --git a/src/main/java/net/minecraft/server/level/ServerChunkCache.java b/src/main/java/net/minecraft/server/level/ServerChunkCache.java index 34174c3cdcb69c96e8601e28ecaf01df9b8c0f37..1b55d1bfc0ebab40dc74a801aa0ad95b6ed22314 100644 --- a/src/main/java/net/minecraft/server/level/ServerChunkCache.java +++ b/src/main/java/net/minecraft/server/level/ServerChunkCache.java @@ -767,7 +767,7 @@ public class ServerChunkCache extends ChunkSource { }; // Paper end this.level.timings.chunkTicks.startTiming(); // Paper - this.chunkMap.getChunks().forEach((playerchunk) -> { // Paper - no... just no... + this.chunkMap.forEachVisibleChunk((playerchunk) -> { // Paper - safe iterator incase chunk loads, also no wrapping Optional optional = ((Either) playerchunk.getTickingChunkFuture().getNow(ChunkHolder.UNLOADED_LEVEL_CHUNK)).left(); if (optional.isPresent()) { diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java index a4d05aeccc142808981f1ecebd001c905ae721ed..e6b7302554b2a54363d55e149744237679262174 100644 --- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java +++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java @@ -288,6 +288,7 @@ public class CraftWorld implements World { @Override public int getTileEntityCount() { + return net.minecraft.server.MCUtil.ensureMain(() -> { // We don't use the full world tile entity list, so we must iterate chunks Long2ObjectLinkedOpenHashMap chunks = world.getChunkSource().chunkMap.visibleChunkMap; int size = 0; @@ -299,6 +300,7 @@ public class CraftWorld implements World { size += chunk.blockEntities.size(); } return size; + }); } @Override @@ -308,6 +310,7 @@ public class CraftWorld implements World { @Override public int getChunkCount() { + return net.minecraft.server.MCUtil.ensureMain(() -> { int ret = 0; for (ChunkHolder chunkHolder : world.getChunkSource().chunkMap.visibleChunkMap.values()) { @@ -316,7 +319,7 @@ public class CraftWorld implements World { } } - return ret; + return ret; }); } @Override @@ -443,6 +446,14 @@ public class CraftWorld implements World { @Override public Chunk[] getLoadedChunks() { + // Paper start + if (Thread.currentThread() != world.getLevel().thread) { + synchronized (world.getChunkSource().chunkMap.visibleChunkMap) { + Long2ObjectLinkedOpenHashMap chunks = world.getChunkSource().chunkMap.visibleChunkMap; + return chunks.values().stream().map(ChunkHolder::getFullChunk).filter(Objects::nonNull).map(net.minecraft.world.level.chunk.LevelChunk::getBukkitChunk).toArray(Chunk[]::new); + } + } + // Paper end Long2ObjectLinkedOpenHashMap chunks = this.world.getChunkSource().chunkMap.visibleChunkMap; return chunks.values().stream().map(ChunkHolder::getFullChunk).filter(Objects::nonNull).map(net.minecraft.world.level.chunk.LevelChunk::getBukkitChunk).toArray(Chunk[]::new); }