From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Aikar Date: Wed, 6 May 2020 04:53:35 -0400 Subject: [PATCH] Optimize Network Manager and add advanced packet support Adds ability for 1 packet to bundle other packets to follow it Adds ability for a packet to delay sending more packets until a state is ready. Removes synchronization from sending packets Removes processing packet queue off of main thread - for the few cases where it is allowed, order is not necessary nor should it even be happening concurrently in first place (handshaking/login/status) Ensures packets sent asynchronously are dispatched on main thread This helps ensure safety for ProtocolLib as packet listeners are commonly accessing world state. This will allow you to schedule a packet to be sent async, but itll be dispatched sync for packet listeners to process. This should solve some deadlock risks Also adds Netty Channel Flush Consolidation to reduce the amount of flushing Also avoids spamming closed channel exception by rechecking closed state in dispatch and then catch exceptions and close if they fire. Part of this commit was authored by: Spottedleaf, sandtechnology diff --git a/net/minecraft/network/Connection.java b/net/minecraft/network/Connection.java index 18f25bc6ada79fd51eb7522a917236299616a371..1672bd0eeea8db44016bbbccf9a332c7f45fdb54 100644 --- a/net/minecraft/network/Connection.java +++ b/net/minecraft/network/Connection.java @@ -85,7 +85,7 @@ public class Connection extends SimpleChannelInboundHandler> { private static final ProtocolInfo INITIAL_PROTOCOL = HandshakeProtocols.SERVERBOUND; private final PacketFlow receiving; private volatile boolean sendLoginDisconnect = true; - private final Queue> pendingActions = Queues.newConcurrentLinkedQueue(); + private final Queue pendingActions = Queues.newConcurrentLinkedQueue(); // Paper - Optimize network public Channel channel; public SocketAddress address; // Spigot start @@ -145,6 +145,10 @@ public class Connection extends SimpleChannelInboundHandler> { } // Paper end - packet limiter @Nullable public SocketAddress haProxyAddress; // Paper - Add API to get player's proxy address + // Paper start - Optimize network + public boolean isPending = true; + public boolean queueImmunity; + // Paper end - Optimize network public Connection(PacketFlow receiving) { this.receiving = receiving; @@ -423,11 +427,38 @@ public class Connection extends SimpleChannelInboundHandler> { } public void send(Packet packet, @Nullable PacketSendListener listener, boolean flush) { - if (this.isConnected()) { - this.flushQueue(); + // Paper start - Optimize network: Handle oversized packets better + final boolean connected = this.isConnected(); + if (!connected && !this.preparing) { + return; + } + + packet.onPacketDispatch(this.getPlayer()); + if (connected && (InnerUtil.canSendImmediate(this, packet) + || (io.papermc.paper.util.MCUtil.isMainThread() && packet.isReady() && this.pendingActions.isEmpty() + && (packet.getExtraPackets() == null || packet.getExtraPackets().isEmpty())))) { this.sendPacket(packet, listener, flush); } else { - this.pendingActions.add(connection -> connection.sendPacket(packet, listener, flush)); + // Write the packets to the queue, then flush - antixray hooks there already + final java.util.List> extraPackets = InnerUtil.buildExtraPackets(packet); + final boolean hasExtraPackets = extraPackets != null && !extraPackets.isEmpty(); + if (!hasExtraPackets) { + this.pendingActions.add(new PacketSendAction(packet, listener, flush)); + } else { + final java.util.List actions = new java.util.ArrayList<>(1 + extraPackets.size()); + actions.add(new PacketSendAction(packet, null, false)); // Delay the future listener until the end of the extra packets + + for (int i = 0, len = extraPackets.size(); i < len;) { + final Packet extraPacket = extraPackets.get(i); + final boolean end = ++i == len; + actions.add(new PacketSendAction(extraPacket, end ? listener : null, end)); // Append listener to the end + } + + this.pendingActions.addAll(actions); + } + + this.flushQueue(); + // Paper end - Optimize network } } @@ -436,7 +467,7 @@ public class Connection extends SimpleChannelInboundHandler> { this.flushQueue(); action.accept(this); } else { - this.pendingActions.add(action); + this.pendingActions.add(new WrappedConsumer(action)); // Paper - Optimize network } } @@ -450,6 +481,14 @@ public class Connection extends SimpleChannelInboundHandler> { } private void doSendPacket(Packet packet, @Nullable PacketSendListener sendListener, boolean flush) { + // Paper start - Optimize network + final net.minecraft.server.level.ServerPlayer player = this.getPlayer(); + if (!this.isConnected()) { + packet.onPacketDispatchFinish(player, null); + return; + } + try { + // Paper end - Optimize network ChannelFuture channelFuture = flush ? this.channel.writeAndFlush(packet) : this.channel.write(packet); if (sendListener != null) { channelFuture.addListener(future -> { @@ -465,14 +504,24 @@ public class Connection extends SimpleChannelInboundHandler> { }); } + // Paper start - Optimize network + if (packet.hasFinishListener()) { + channelFuture.addListener((ChannelFutureListener) future -> packet.onPacketDispatchFinish(player, future)); + } channelFuture.addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE); + } catch (final Exception e) { + LOGGER.error("NetworkException: {}", player, e); + this.disconnect(Component.translatable("disconnect.genericReason", "Internal Exception: " + e.getMessage())); + packet.onPacketDispatchFinish(player, null); + } + // Paper end - Optimize network } public void flushChannel() { if (this.isConnected()) { this.flush(); } else { - this.pendingActions.add(Connection::flush); + this.pendingActions.add(new WrappedConsumer(Connection::flush)); // Paper - Optimize network } } @@ -484,16 +533,57 @@ public class Connection extends SimpleChannelInboundHandler> { } } - private void flushQueue() { - if (this.channel != null && this.channel.isOpen()) { + // Paper start - Optimize network: Rewrite this to be safer if ran off main thread + private boolean flushQueue() { + if (!this.isConnected()) { + return true; + } + if (io.papermc.paper.util.MCUtil.isMainThread()) { + return this.processQueue(); + } else if (this.isPending) { + // Should only happen during login/status stages synchronized (this.pendingActions) { - Consumer consumer; - while ((consumer = this.pendingActions.poll()) != null) { - consumer.accept(this); + return this.processQueue(); + } + } + return false; + } + + private boolean processQueue() { + if (this.pendingActions.isEmpty()) { + return true; + } + + // If we are on main, we are safe here in that nothing else should be processing queue off main anymore + // But if we are not on main due to login/status, the parent is synchronized on packetQueue + final java.util.Iterator iterator = this.pendingActions.iterator(); + while (iterator.hasNext()) { + final WrappedConsumer queued = iterator.next(); // poll -> peek + + // Fix NPE (Spigot bug caused by handleDisconnection()) + if (queued == null) { + return true; + } + + if (queued.isConsumed()) { + continue; + } + + if (queued instanceof PacketSendAction packetSendAction) { + final Packet packet = packetSendAction.packet; + if (!packet.isReady()) { + return false; } } + + iterator.remove(); + if (queued.tryMarkConsumed()) { + queued.accept(this); + } } + return true; } + // Paper end - Optimize network private static final int MAX_PER_TICK = io.papermc.paper.configuration.GlobalConfiguration.get().misc.maxJoinsPerTick; // Paper - Buffer joins to world private static int joinAttemptsThisTick; // Paper - Buffer joins to world @@ -557,6 +647,7 @@ public class Connection extends SimpleChannelInboundHandler> { public void disconnect(DisconnectionDetails disconnectionDetails) { this.preparing = false; // Spigot + this.clearPacketQueue(); // Paper - Optimize network if (this.channel == null) { this.delayedDisconnect = disconnectionDetails; } @@ -745,7 +836,7 @@ public class Connection extends SimpleChannelInboundHandler> { public void handleDisconnection() { if (this.channel != null && !this.channel.isOpen()) { if (this.disconnectionHandled) { - LOGGER.warn("handleDisconnection() called twice"); + // LOGGER.warn("handleDisconnection() called twice"); // Paper - Don't log useless message } else { this.disconnectionHandled = true; PacketListener packetListener = this.getPacketListener(); @@ -756,7 +847,7 @@ public class Connection extends SimpleChannelInboundHandler> { ); packetListener1.onDisconnect(disconnectionDetails); } - this.pendingActions.clear(); // Free up packet queue. + this.clearPacketQueue(); // Paper - Optimize network // Paper start - Add PlayerConnectionCloseEvent if (packetListener instanceof net.minecraft.server.network.ServerCommonPacketListenerImpl commonPacketListener) { /* Player was logged in, either game listener or configuration listener */ @@ -791,4 +882,93 @@ public class Connection extends SimpleChannelInboundHandler> { public void setBandwidthLogger(LocalSampleLogger bandwithLogger) { this.bandwidthDebugMonitor = new BandwidthDebugMonitor(bandwithLogger); } + + // Paper start - Optimize network + public void clearPacketQueue() { + final net.minecraft.server.level.ServerPlayer player = getPlayer(); + for (final Consumer queuedAction : this.pendingActions) { + if (queuedAction instanceof PacketSendAction packetSendAction) { + final Packet packet = packetSendAction.packet; + if (packet.hasFinishListener()) { + packet.onPacketDispatchFinish(player, null); + } + } + } + this.pendingActions.clear(); + } + + private static class InnerUtil { // Attempt to hide these methods from ProtocolLib, so it doesn't accidently pick them up. + + @Nullable + private static java.util.List> buildExtraPackets(final Packet packet) { + final java.util.List> extra = packet.getExtraPackets(); + if (extra == null || extra.isEmpty()) { + return null; + } + + final java.util.List> ret = new java.util.ArrayList<>(1 + extra.size()); + buildExtraPackets0(extra, ret); + return ret; + } + + private static void buildExtraPackets0(final java.util.List> extraPackets, final java.util.List> into) { + for (final Packet extra : extraPackets) { + into.add(extra); + final java.util.List> extraExtra = extra.getExtraPackets(); + if (extraExtra != null && !extraExtra.isEmpty()) { + buildExtraPackets0(extraExtra, into); + } + } + } + + private static boolean canSendImmediate(final Connection networkManager, final net.minecraft.network.protocol.Packet packet) { + return networkManager.isPending || networkManager.packetListener.protocol() != ConnectionProtocol.PLAY || + packet instanceof net.minecraft.network.protocol.common.ClientboundKeepAlivePacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundPlayerChatPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSystemChatPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundCommandSuggestionsPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSetTitleTextPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSetSubtitleTextPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSetActionBarTextPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSetTitlesAnimationPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundClearTitlesPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSoundPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundSoundEntityPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundStopSoundPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundLevelParticlesPacket || + packet instanceof net.minecraft.network.protocol.game.ClientboundBossEventPacket; + } + } + + private static class WrappedConsumer implements Consumer { + private final Consumer delegate; + private final java.util.concurrent.atomic.AtomicBoolean consumed = new java.util.concurrent.atomic.AtomicBoolean(false); + + private WrappedConsumer(final Consumer delegate) { + this.delegate = delegate; + } + + @Override + public void accept(final Connection connection) { + this.delegate.accept(connection); + } + + public boolean tryMarkConsumed() { + return consumed.compareAndSet(false, true); + } + + public boolean isConsumed() { + return consumed.get(); + } + } + + private static final class PacketSendAction extends WrappedConsumer { + private final Packet packet; + + private PacketSendAction(final Packet packet, @Nullable final PacketSendListener packetSendListener, final boolean flush) { + super(connection -> connection.sendPacket(packet, packetSendListener, flush)); + this.packet = packet; + } + } + // Paper end - Optimize network } diff --git a/net/minecraft/network/protocol/Packet.java b/net/minecraft/network/protocol/Packet.java index 65ff8b9112ec76eeac48c679044fc02ae7d4ffeb..e4789584cbe43959681a8522c66eab58369bebd0 100644 --- a/net/minecraft/network/protocol/Packet.java +++ b/net/minecraft/network/protocol/Packet.java @@ -35,4 +35,32 @@ public interface Packet { static > StreamCodec codec(StreamMemberEncoder encoder, StreamDecoder decoder) { return StreamCodec.ofMember(encoder, decoder); } + + // Paper start + /** + * @param player Null if not at PLAY stage yet + */ + default void onPacketDispatch(@org.jetbrains.annotations.Nullable net.minecraft.server.level.ServerPlayer player) { + } + + /** + * @param player Null if not at PLAY stage yet + * @param future Can be null if packet was cancelled + */ + default void onPacketDispatchFinish(@org.jetbrains.annotations.Nullable net.minecraft.server.level.ServerPlayer player, @org.jetbrains.annotations.Nullable io.netty.channel.ChannelFuture future) { + } + + default boolean hasFinishListener() { + return false; + } + + default boolean isReady() { + return true; + } + + @org.jetbrains.annotations.Nullable + default java.util.List> getExtraPackets() { + return null; + } + // Paper end } diff --git a/net/minecraft/server/network/ServerConnectionListener.java b/net/minecraft/server/network/ServerConnectionListener.java index 18fa53903cd6500ae65d993a6fe7f49d6b069339..b68adf37af7172671163d4a8074d2bfa97724b4b 100644 --- a/net/minecraft/server/network/ServerConnectionListener.java +++ b/net/minecraft/server/network/ServerConnectionListener.java @@ -66,11 +66,13 @@ public class ServerConnectionListener { // Paper start - prevent blocking on adding a new connection while the server is ticking private final java.util.Queue pending = new java.util.concurrent.ConcurrentLinkedQueue<>(); + private static final boolean disableFlushConsolidation = Boolean.getBoolean("Paper.disableFlushConsolidate"); // Paper - Optimize network private final void addPending() { Connection connection; while ((connection = this.pending.poll()) != null) { this.connections.add(connection); + connection.isPending = false; // Paper - Optimize network } } // Paper end - prevent blocking on adding a new connection while the server is ticking @@ -120,6 +122,7 @@ public class ServerConnectionListener { } catch (ChannelException var5) { } + if (!disableFlushConsolidation) channel.pipeline().addFirst(new io.netty.handler.flush.FlushConsolidationHandler()); // Paper - Optimize network ChannelPipeline channelPipeline = channel.pipeline().addLast("timeout", new ReadTimeoutHandler(30)); if (ServerConnectionListener.this.server.repliesToStatus()) { channelPipeline.addLast("legacy_query", new LegacyQueryHandler(ServerConnectionListener.this.getServer()));