From d4a80e85b8785b079769629ecf004f73fde66efd 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/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java index 1dcd0980ec..59055cccc5 100644 --- a/src/main/java/net/minecraft/server/ChunkProviderServer.java +++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java @@ -669,7 +669,7 @@ public class ChunkProviderServer extends IChunkProvider { entityPlayer.playerNaturallySpawnedEvent.callEvent(); }; // Paper end - this.playerChunkMap.f().forEach((playerchunk) -> { + this.playerChunkMap.visibleChunks.values().forEach((playerchunk) -> { // Paper - no need to wrap iterator Optional optional = ((Either) playerchunk.b().getNow(PlayerChunk.UNLOADED_CHUNK)).left(); if (optional.isPresent()) { diff --git a/src/main/java/net/minecraft/server/MCUtil.java b/src/main/java/net/minecraft/server/MCUtil.java index b9d5844520..9980e4c277 100644 --- a/src/main/java/net/minecraft/server/MCUtil.java +++ b/src/main/java/net/minecraft/server/MCUtil.java @@ -500,7 +500,7 @@ public final class MCUtil { WorldServer world = ((org.bukkit.craftbukkit.CraftWorld)bukkitWorld).getHandle(); PlayerChunkMap chunkMap = world.getChunkProvider().playerChunkMap; - Long2ObjectLinkedOpenHashMap visibleChunks = chunkMap.visibleChunks; + Long2ObjectLinkedOpenHashMap visibleChunks = chunkMap.getVisibleChunks(); ChunkMapDistance chunkMapDistance = chunkMap.getChunkMapDistanceManager(); List allChunks = new ArrayList<>(visibleChunks.values()); List players = world.players; diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java index e1e4ea793a..0aa6487d5b 100644 --- a/src/main/java/net/minecraft/server/PlayerChunkMap.java +++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java @@ -56,7 +56,8 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { private static final Logger LOGGER = LogManager.getLogger(); public static final int GOLDEN_TICKET = 33 + ChunkStatus.b(); public final Long2ObjectLinkedOpenHashMap updatingChunks = new Long2ObjectLinkedOpenHashMap(); - public volatile Long2ObjectLinkedOpenHashMap visibleChunks; + public final Long2ObjectLinkedOpenHashMap visibleChunks = new Long2ObjectLinkedOpenHashMap(); // Paper - remove copying, make mt safe + public volatile Long2ObjectLinkedOpenHashMap visibleChunksClone; // Paper - remove copying, make mt safe private final Long2ObjectLinkedOpenHashMap pendingUnload; final LongSet loadedChunks; // Paper - private -> package public final WorldServer world; @@ -170,7 +171,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { public PlayerChunkMap(WorldServer worldserver, File file, DataFixer datafixer, DefinedStructureManager definedstructuremanager, Executor executor, IAsyncTaskHandler iasynctaskhandler, ILightAccess ilightaccess, ChunkGenerator chunkgenerator, WorldLoadListener worldloadlistener, Supplier supplier, int i) { super(new File(worldserver.getWorldProvider().getDimensionManager().a(file), "region"), datafixer); - this.visibleChunks = this.updatingChunks.clone(); + //this.visibleChunks = this.updatingChunks.clone(); // Paper - no more cloning this.pendingUnload = new Long2ObjectLinkedOpenHashMap(); this.loadedChunks = new LongOpenHashSet(); this.unloadQueue = new LongOpenHashSet(); @@ -262,8 +263,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { return (PlayerChunk) this.updatingChunks.get(i); } + // 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"); + public Long2ObjectLinkedOpenHashMap getVisibleChunks() { + if (Thread.currentThread() == this.world.serverThread) { + return this.visibleChunks; + } else { + synchronized (this.visibleChunks) { + if (DEBUG_ASYNC_VISIBLE_CHUNKS) new Throwable("Async getVisibleChunks").printStackTrace(); + if (this.visibleChunksClone == null) { + this.visibleChunksClone = this.visibleChunks.clone(); + } + return this.visibleChunksClone; + } + } + } + // Paper end + @Nullable public PlayerChunk getVisibleChunk(long i) { // Paper - protected -> public + // Paper start - mt safe get + if (Thread.currentThread() != this.world.serverThread) { + synchronized (this.visibleChunks) { + return (PlayerChunk) this.visibleChunks.get(i); + } + } + // Paper end return (PlayerChunk) this.visibleChunks.get(i); } @@ -444,8 +469,9 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { // Paper end protected void save(boolean flag) { + Long2ObjectLinkedOpenHashMap visibleChunks = this.getVisibleChunks(); // Paper remove clone of visible Chunks unless saving off main thread (watchdog kill) if (flag) { - List list = (List) this.visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).peek(PlayerChunk::m).collect(Collectors.toList()); + List list = (List) visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).peek(PlayerChunk::m).collect(Collectors.toList()); // Paper - remove cloning of visible chunks MutableBoolean mutableboolean = new MutableBoolean(); do { @@ -473,7 +499,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { // this.i(); // Paper - nuke IOWorker PlayerChunkMap.LOGGER.info("ThreadedAnvilChunkStorage ({}): All chunks are saved", this.w.getName()); } else { - this.visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).forEach((playerchunk) -> { + visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).forEach((playerchunk) -> { IChunkAccess ichunkaccess = (IChunkAccess) playerchunk.getChunkSave().getNow(null); // CraftBukkit - decompile error if (ichunkaccess instanceof ProtoChunkExtension || ichunkaccess instanceof Chunk) { @@ -643,7 +669,14 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { if (!this.updatingChunksModified) { return false; } else { - this.visibleChunks = this.updatingChunks.clone(); + // Paper start - stop cloning visibleChunks + synchronized (this.visibleChunks) { + this.visibleChunks.clear(); + this.visibleChunks.putAll(this.updatingChunks); + this.visibleChunksClone = null; + } + // Paper end + this.updatingChunksModified = false; return true; } @@ -1104,12 +1137,12 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d { } protected Iterable f() { - return Iterables.unmodifiableIterable(this.visibleChunks.values()); + return Iterables.unmodifiableIterable(this.getVisibleChunks().values()); // Paper } void a(Writer writer) throws IOException { CSVWriter csvwriter = CSVWriter.a().a("x").a("z").a("level").a("in_memory").a("status").a("full_status").a("accessible_ready").a("ticking_ready").a("entity_ticking_ready").a("ticket").a("spawning").a("entity_count").a("block_entity_count").a(writer); - ObjectBidirectionalIterator objectbidirectionaliterator = this.visibleChunks.long2ObjectEntrySet().iterator(); + ObjectBidirectionalIterator objectbidirectionaliterator = this.getVisibleChunks().long2ObjectEntrySet().iterator(); // Paper while (objectbidirectionaliterator.hasNext()) { Entry entry = (Entry) objectbidirectionaliterator.next(); diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java index 051506fce8..c0e8eb85d7 100644 --- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java +++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java @@ -290,6 +290,7 @@ public class CraftWorld implements World { return ret; } public int getTileEntityCount() { + org.spigotmc.AsyncCatcher.catchOp("getTileEntityCount"); // We don't use the full world tile entity list, so we must iterate chunks Long2ObjectLinkedOpenHashMap chunks = world.getChunkProvider().playerChunkMap.visibleChunks; int size = 0; @@ -306,6 +307,7 @@ public class CraftWorld implements World { return world.tileEntityListTick.size(); } public int getChunkCount() { + org.spigotmc.AsyncCatcher.catchOp("getChunkCount"); int ret = 0; for (PlayerChunk chunkHolder : world.getChunkProvider().playerChunkMap.visibleChunks.values()) { @@ -432,6 +434,7 @@ public class CraftWorld implements World { @Override public Chunk[] getLoadedChunks() { + org.spigotmc.AsyncCatcher.catchOp("getLoadedChunks"); // Paper Long2ObjectLinkedOpenHashMap chunks = world.getChunkProvider().playerChunkMap.visibleChunks; return chunks.values().stream().map(PlayerChunk::getFullChunk).filter(Objects::nonNull).map(net.minecraft.server.Chunk::getBukkitChunk).toArray(Chunk[]::new); } -- 2.25.1