From 4b72c68d1947dece956e521879a05cc2e1fc17aa Mon Sep 17 00:00:00 2001 From: Aikar Date: Sun, 16 Sep 2018 00:00:16 -0400 Subject: [PATCH] Optimize and Fix ExpiringMap Issues computeIfAbsent would leak as the entry was never registered into the ttl map, as well as some other methods were at risk, so they were added. This also synchronizes all access make the map thread safe. This also redesigns cleaning to not run on every manipulation, and instead to run clean once per tick per active expiring map. diff --git a/src/main/java/net/minecraft/server/ExpiringMap.java b/src/main/java/net/minecraft/server/ExpiringMap.java index 4006f5a69c..127de5c8df 100644 --- a/src/main/java/net/minecraft/server/ExpiringMap.java +++ b/src/main/java/net/minecraft/server/ExpiringMap.java @@ -2,38 +2,163 @@ package net.minecraft.server; import it.unimi.dsi.fastutil.longs.Long2LongLinkedOpenHashMap; import it.unimi.dsi.fastutil.longs.Long2LongMap; +import it.unimi.dsi.fastutil.longs.Long2ObjectMaps; import it.unimi.dsi.fastutil.longs.Long2ObjectOpenHashMap; -import it.unimi.dsi.fastutil.longs.Long2LongMap.Entry; import it.unimi.dsi.fastutil.objects.ObjectIterator; import java.util.Map; +import java.util.function.BiFunction; +import java.util.function.Function; +import java.util.function.LongFunction; -public class ExpiringMap extends Long2ObjectOpenHashMap { +public class ExpiringMap extends Long2ObjectMaps.SynchronizedMap { // paper - synchronize accesss private final int a; - private final Long2LongMap b = new Long2LongLinkedOpenHashMap(); + private final Long2LongMap ttl = new Long2LongLinkedOpenHashMap(); // Paper public ExpiringMap(int i, int j) { - super(i); + super(new Long2ObjectOpenHashMap<>(i)); // Paper this.a = j; } + // Paper start + private void setAccess(long i) { a(i); } // Paper - OBFHELPER private void a(long i) { - long j = SystemUtils.b(); - this.b.put(i, j); - ObjectIterator objectiterator = this.b.long2LongEntrySet().iterator(); - - while(objectiterator.hasNext()) { - Entry entry = (Entry)objectiterator.next(); - Object object = super.get(entry.getLongKey()); - if (j - entry.getLongValue() <= (long)this.a) { - break; + synchronized (this.sync) { + long j = System.currentTimeMillis(); // Paper + this.ttl.put(i, j); + if (!registered) { + registered = true; + MinecraftServer.getServer().expiringMaps.add(this); } + } + } - if (object != null && this.a(object)) { - super.remove(entry.getLongKey()); - objectiterator.remove(); - } + @Override + public T compute(long l, BiFunction biFunction) { + setAccess(l); + return super.compute(l, biFunction); + } + + @Override + public T putIfAbsent(long l, T t) { + setAccess(l); + return super.putIfAbsent(l, t); + } + + @Override + public T computeIfPresent(long l, BiFunction biFunction) { + setAccess(l); + return super.computeIfPresent(l, biFunction); + } + + @Override + public T computeIfAbsent(long l, LongFunction longFunction) { + setAccess(l); + return super.computeIfAbsent(l, longFunction); + } + + @Override + public boolean replace(long l, T t, T v1) { + setAccess(l); + return super.replace(l, t, v1); + } + + @Override + public T replace(long l, T t) { + setAccess(l); + return super.replace(l, t); + } + + @Override + public T putIfAbsent(Long aLong, T t) { + setAccess(aLong); + return super.putIfAbsent(aLong, t); + } + + @Override + public boolean replace(Long aLong, T t, T v1) { + setAccess(aLong); + return super.replace(aLong, t, v1); + } + + @Override + public T replace(Long aLong, T t) { + setAccess(aLong); + return super.replace(aLong, t); + } + + @Override + public T computeIfAbsent(Long aLong, Function function) { + setAccess(aLong); + return super.computeIfAbsent(aLong, function); + } + + @Override + public T computeIfPresent(Long aLong, BiFunction biFunction) { + setAccess(aLong); + return super.computeIfPresent(aLong, biFunction); + } + + @Override + public T compute(Long aLong, BiFunction biFunction) { + setAccess(aLong); + return super.compute(aLong, biFunction); + } + + @Override + public void clear() { + synchronized (this.sync) { + ttl.clear(); + super.clear(); } + } + private boolean registered = false; + private boolean hasLeaked = false; + + // Break clean to its own method to be ticked + boolean clean() { + synchronized (this.sync) { + long now = System.currentTimeMillis(); + ObjectIterator objectiterator = this.ttl.long2LongEntrySet().iterator(); // Paper + + while (objectiterator.hasNext()) { + Long2LongMap.Entry entry = objectiterator.next(); // Paper + T object = super.get(entry.getLongKey()); // Paper + if (now - entry.getLongValue() <= (long) this.a) { + break; + } + + if (object != null && this.a(object)) { + super.remove(entry.getLongKey()); + objectiterator.remove(); + } + } + int ttlSize = this.ttl.size(); + int thisSize = this.size(); + if (ttlSize < thisSize) { + if (!hasLeaked) { // log once + hasLeaked = true; + MinecraftServer.LOGGER.warn("WARNING: ExpiringMap desync (" + ttlSize + ":" + thisSize + ")- Memory leak risk! We will recover from this, but this means there is still a bug. Please do not open an issue about this. Mention it in Discord (we don't need everyone reporting the same thing)"); + } + try { + for (Entry entry : this.long2ObjectEntrySet()) { + ttl.putIfAbsent(entry.getLongKey(), now); + } + } catch (Exception e) { + } // Ignore any como's + } else if (ttlSize > this.size()) { + try { + this.ttl.long2LongEntrySet().removeIf(entry -> !this.containsKey(entry.getLongKey())); + } catch (Exception e) { + } // Ignore any como's + } + if (isEmpty()) { + registered = false; + return true; + } + return false; + } + // Paper end } protected boolean a(T var1) { @@ -51,8 +176,13 @@ public class ExpiringMap extends Long2ObjectOpenHashMap { } public T get(long i) { - this.a(i); - return (T)super.get(i); + // Paper start - don't setAccess unless a hit + T t = super.get(i); + if (t != null) { + this.setAccess(i); + } + return t; + // Paper end } public void putAll(Map var1) { diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java index eb3fc836fb..81cda5df56 100644 --- a/src/main/java/net/minecraft/server/MinecraftServer.java +++ b/src/main/java/net/minecraft/server/MinecraftServer.java @@ -155,6 +155,7 @@ public abstract class MinecraftServer implements IAsyncTaskHandler, IMojangStati public int autosavePeriod; public File bukkitDataPackFolder; public CommandDispatcher vanillaCommandDispatcher; + public List expiringMaps = java.util.Collections.synchronizedList(new java.util.ArrayList<>()); // PAper // CraftBukkit end // Spigot start public static final int TPS = 20; @@ -999,6 +1000,7 @@ public abstract class MinecraftServer implements IAsyncTaskHandler, IMojangStati this.methodProfiler.e(); org.spigotmc.WatchdogThread.tick(); // Spigot PaperLightingQueue.processQueue(startTime); // Paper + expiringMaps.removeIf(ExpiringMap::clean); // Paper this.slackActivityAccountant.tickEnded(l); // Spigot co.aikar.timings.TimingsManager.FULL_SERVER_TICK.stopTiming(); // Paper } -- 2.19.0