ege-st commented on code in PR #11496: URL: https://github.com/apache/pinot/pull/11496#discussion_r1320236084
########## pinot-core/src/main/java/org/apache/pinot/core/transport/DirectOOMHandler.java: ########## @@ -0,0 +1,94 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +package org.apache.pinot.core.transport; + +import io.netty.channel.Channel; +import io.netty.channel.ChannelHandlerContext; +import io.netty.channel.ChannelInboundHandlerAdapter; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.atomic.AtomicBoolean; +import org.apache.pinot.spi.exception.QueryCancelledException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +// Handling netty direct memory OOM. In this case there is a great chance that multiple channels are receiving +// large data tables from servers concurrently. We want to close all channels to servers to proactively release +// the direct memory, because the execution of netty threads can deadlock in allocating direct memory, in which case +// no one will reach channelRead0. +public class DirectOOMHandler extends ChannelInboundHandlerAdapter { + private static final Logger LOGGER = LoggerFactory.getLogger(DataTableHandler.class); + private static final AtomicBoolean DIRECT_OOM_SHUTTING_DOWN = new AtomicBoolean(false); + private final QueryRouter _queryRouter; + private final ServerRoutingInstance _serverRoutingInstance; + private final ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> _serverToChannelMap; + + public void setSilentShutDown() { + _silentShutDown = true; + } + + private volatile boolean _silentShutDown = false; + + public DirectOOMHandler(QueryRouter queryRouter, ServerRoutingInstance serverRoutingInstance, + ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> serverToChannelMap) { + _queryRouter = queryRouter; + _serverRoutingInstance = serverRoutingInstance; + _serverToChannelMap = serverToChannelMap; + } + + @Override + public void channelInactive(ChannelHandlerContext ctx) { + if (_silentShutDown) { + return; + } + ctx.fireChannelInactive(); + } + + @Override + public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { + // catch direct memory oom here + if (cause instanceof OutOfMemoryError && cause.getMessage().contains("Direct buffer")) { Review Comment: Is doing a substring match a reliable way of determining if the error is a direct memory OOM? ########## pinot-core/src/main/java/org/apache/pinot/core/transport/DirectOOMHandler.java: ########## @@ -0,0 +1,94 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +package org.apache.pinot.core.transport; + +import io.netty.channel.Channel; +import io.netty.channel.ChannelHandlerContext; +import io.netty.channel.ChannelInboundHandlerAdapter; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.atomic.AtomicBoolean; +import org.apache.pinot.spi.exception.QueryCancelledException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +// Handling netty direct memory OOM. In this case there is a great chance that multiple channels are receiving +// large data tables from servers concurrently. We want to close all channels to servers to proactively release +// the direct memory, because the execution of netty threads can deadlock in allocating direct memory, in which case +// no one will reach channelRead0. +public class DirectOOMHandler extends ChannelInboundHandlerAdapter { + private static final Logger LOGGER = LoggerFactory.getLogger(DataTableHandler.class); + private static final AtomicBoolean DIRECT_OOM_SHUTTING_DOWN = new AtomicBoolean(false); + private final QueryRouter _queryRouter; + private final ServerRoutingInstance _serverRoutingInstance; + private final ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> _serverToChannelMap; + + public void setSilentShutDown() { + _silentShutDown = true; + } + + private volatile boolean _silentShutDown = false; + + public DirectOOMHandler(QueryRouter queryRouter, ServerRoutingInstance serverRoutingInstance, + ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> serverToChannelMap) { + _queryRouter = queryRouter; + _serverRoutingInstance = serverRoutingInstance; + _serverToChannelMap = serverToChannelMap; + } + + @Override + public void channelInactive(ChannelHandlerContext ctx) { + if (_silentShutDown) { + return; + } + ctx.fireChannelInactive(); + } + + @Override + public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { + // catch direct memory oom here + if (cause instanceof OutOfMemoryError && cause.getMessage().contains("Direct buffer")) { + // only one thread can get here and do the shutdown + if (DIRECT_OOM_SHUTTING_DOWN.compareAndSet(false, true)) { + try { + // close all channels to servers + ctx.channel().close(); + _serverToChannelMap.keySet().forEach(serverRoutingInstance -> { + Channel channel = _serverToChannelMap.get(serverRoutingInstance)._channel; + if (channel != null) { + channel.pipeline().get(DirectOOMHandler.class).setSilentShutDown(); + channel.close(); + } + _serverToChannelMap.remove(serverRoutingInstance); + }); + _queryRouter.markServerDown(_serverRoutingInstance, + new QueryCancelledException("Query cancelled as broker is out of direct memory")); + LOGGER.error("Closing ALL channels to servers, as we are running out of direct memory " + + "while receiving response from {}", _serverRoutingInstance); Review Comment: We should record this log message before closing the channels, that way, if something happens while closing we have the log message to tell us that the Broker had entered into the channel reset state. ########## pinot-core/src/main/java/org/apache/pinot/core/transport/DirectOOMHandler.java: ########## @@ -0,0 +1,94 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ +package org.apache.pinot.core.transport; + +import io.netty.channel.Channel; +import io.netty.channel.ChannelHandlerContext; +import io.netty.channel.ChannelInboundHandlerAdapter; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.atomic.AtomicBoolean; +import org.apache.pinot.spi.exception.QueryCancelledException; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + + +// Handling netty direct memory OOM. In this case there is a great chance that multiple channels are receiving +// large data tables from servers concurrently. We want to close all channels to servers to proactively release +// the direct memory, because the execution of netty threads can deadlock in allocating direct memory, in which case +// no one will reach channelRead0. +public class DirectOOMHandler extends ChannelInboundHandlerAdapter { + private static final Logger LOGGER = LoggerFactory.getLogger(DataTableHandler.class); + private static final AtomicBoolean DIRECT_OOM_SHUTTING_DOWN = new AtomicBoolean(false); + private final QueryRouter _queryRouter; + private final ServerRoutingInstance _serverRoutingInstance; + private final ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> _serverToChannelMap; + + public void setSilentShutDown() { + _silentShutDown = true; + } + + private volatile boolean _silentShutDown = false; + + public DirectOOMHandler(QueryRouter queryRouter, ServerRoutingInstance serverRoutingInstance, + ConcurrentHashMap<ServerRoutingInstance, ServerChannels.ServerChannel> serverToChannelMap) { + _queryRouter = queryRouter; + _serverRoutingInstance = serverRoutingInstance; + _serverToChannelMap = serverToChannelMap; + } + + @Override + public void channelInactive(ChannelHandlerContext ctx) { + if (_silentShutDown) { + return; + } + ctx.fireChannelInactive(); + } + + @Override + public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { + // catch direct memory oom here + if (cause instanceof OutOfMemoryError && cause.getMessage().contains("Direct buffer")) { + // only one thread can get here and do the shutdown + if (DIRECT_OOM_SHUTTING_DOWN.compareAndSet(false, true)) { Review Comment: The situation where this will evaluate to `false` is when a channel gets a DM OOM after another channel has OOMed so the channel shutdown process has already started? Should we have a log event for that? The channels are already being reset but I think we'd still want to know all the connections that got OOMed. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
