The core problem is our consumers stop consuming and lag increases. We found this blog: https://cwiki.apache.org/confluence/display/KAFKA/FAQ#FAQ-Myconsumerseemstohavestopped,why?. This lists 3 possibilities.
The blog also talks earlier about spurious rebalances, due to improper GC settings, but we couldn't find what GC settings to use. We are considering changing the zookeeper timeouts. We are a little confused about the various issues, the sequence of issues and what could cause the consumers to stop reading. If the fetchers get shutdown, due to a ClosedByInterruptException in the "leader_finder" thread, which tells the "executor_watcher" thread to shutdown the fetchers, that would be another reason the consumers stop processing data. Is this possible? Thank you, rob -----Original Message----- From: Seshadri, Balaji [mailto:balaji.sesha...@dish.com] Sent: Friday, January 10, 2014 11:40 AM To: users@kafka.apache.org Subject: RE: Looks like consumer fetchers get stopped we are not getting any data It would be helpful if you guys can shed some light why all fetchers are getting stopped. -----Original Message----- From: Seshadri, Balaji [mailto:balaji.sesha...@dish.com] Sent: Friday, January 10, 2014 11:28 AM To: users@kafka.apache.org Subject: RE: Looks like consumer fetchers get stopped we are not getting any data We also got the below error when this happens. {2014-01-10 00:58:11,292} INFO [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b_watcher_executor] (?:?) - [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b], exception during rebalance org.I0Itec.zkclient.exception.ZkNoNodeException: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /consumers/account-info-updated-hadoop-consumer/ids/account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b at org.I0Itec.zkclient.exception.ZkException.create(ZkException.java:47) at org.I0Itec.zkclient.ZkClient.retryUntilConnected(ZkClient.java:685) at org.I0Itec.zkclient.ZkClient.readData(ZkClient.java:766) at org.I0Itec.zkclient.ZkClient.readData(ZkClient.java:761) at kafka.utils.ZkUtils$.readData(Unknown Source) at kafka.consumer.TopicCount$.constructTopicCount(Unknown Source) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.kafka$consumer$ZookeeperConsumerConnector$ZKRebalancerListener$$rebalance(Unknown Source) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anonfun$syncedRebalance$1.apply$mcVI$sp(Unknown Source) at scala.collection.immutable.Range.foreach$mVc$sp(Range.scala:142) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener.syncedRebalance(Unknown Source) at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anon$1.run(Unknown Source) Caused by: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /consumers/account-info-updated-hadoop-consumer/ids/account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b at org.apache.zookeeper.KeeperException.create(KeeperException.java:102) at org.apache.zookeeper.KeeperException.create(KeeperException.java:42) at org.apache.zookeeper.ZooKeeper.getData(ZooKeeper.java:927) at org.apache.zookeeper.ZooKeeper.getData(ZooKeeper.java:956) at org.I0Itec.zkclient.ZkConnection.readData(ZkConnection.java:103) at org.I0Itec.zkclient.ZkClient$9.call(ZkClient.java:770) at org.I0Itec.zkclient.ZkClient$9.call(ZkClient.java:766) at org.I0Itec.zkclient.ZkClient.retryUntilConnected(ZkClient.java:675) ... 9 more -----Original Message----- From: Seshadri, Balaji [mailto:balaji.sesha...@dish.com] Sent: Friday, January 10, 2014 10:52 AM To: users@kafka.apache.org Subject: Looks like consumer fetchers get stopped we are not getting any data Please let us know why we are not getting any data from Kafaka after this log from Kafka,can you guys lets us know. What could be causing all fetchers associated to be stooped why it is not doing retry. {2014-01-10 00:58:09,284} WARN [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b-leader-finder-thread] (?:?) - Fetching topic metadata with correlation id 3 for topics [Set(account-info-updated)] from broker [id:1,host:tm1-kafkabroker101,port:9092] failed java.nio.channels.ClosedByInterruptException at java.nio.channels.spi.AbstractInterruptibleChannel.end(AbstractInterruptibleChannel.java:202) at sun.nio.ch.SocketChannelImpl.write(SocketChannelImpl.java:506) at java.nio.channels.SocketChannel.write(SocketChannel.java:493) at kafka.network.BoundedByteBufferSend.writeTo(Unknown Source) at kafka.network.Send$class.writeCompletely(Unknown Source) at kafka.network.BoundedByteBufferSend.writeCompletely(Unknown Source) at kafka.network.BlockingChannel.send(Unknown Source) at kafka.producer.SyncProducer.liftedTree1$1(Unknown Source) at kafka.producer.SyncProducer.kafka$producer$SyncProducer$$doSend(Unknown Source) at kafka.producer.SyncProducer.send(Unknown Source) at kafka.client.ClientUtils$.fetchTopicMetadata(Unknown Source) at kafka.client.ClientUtils$.fetchTopicMetadata(Unknown Source) at kafka.consumer.ConsumerFetcherManager$LeaderFinderThread.doWork(Unknown Source) at kafka.utils.ShutdownableThread.run(Unknown Source) {2014-01-10 00:58:09,284} DEBUG [account-access-hadoop-consumer_tm1mwdpl04-1389222551916-a0c87abc_watcher_executor] (?:?) - initial fetch offset of account-access:27: fetched offset = 9655: consumed offset = 9655 is 9655 {2014-01-10 00:58:09,284} DEBUG [bill-generated-hadoop-consumer_tm1mwdpl04-1389222547995-29a6dce9_watcher_executor] (?:?) - initial consumer offset of bill-generated:11: fetched offset = 152: consumed offset = 152 is 152 {2014-01-10 00:58:09,284} DEBUG [outbound-communications-hadoop-consumer_tm1mwdpl04-1389222550693-8bc34b77_watcher_executor] (?:?) - [outbound-communications-hadoop-consumer_tm1mwdpl04-1389222550693-8bc34b77], outbound-communications:108: fetched offset = 1689: consumed offset = 1689 selected new offset 1689 {2014-01-10 00:58:09,284} DEBUG [catalina-exec-3-SendThread(tvip-m1-mw-zookeeper.dish.com:2181)] (ClientCnxn.java:839) - Reading reply sessionid:0x1434b49cf56383b, packet:: clientPath:null serverPath:null finished:false header:: 279,4 replyHeader:: 279,51539617506,0 request:: '/consumers/outbound-call-attempted-hadoop-consumer/offsets/outbound-call-attempted/14,F response:: #30,s{39860186414,39860186414,1387517714994,1387517714994,0,0,0,0,1,0,39860186414} {2014-01-10 00:58:09,285} INFO [outbound-communications-hadoop-consumer_tm1mwdpl04-1389222550693-8bc34b77_watcher_executor] (?:?) - [outbound-communications-hadoop-consumer_tm1mwdpl04-1389222550693-8bc34b77], outbound-communications-hadoop-consumer_tm1mwdpl04-1389222550693-8bc34b77-3 attempting to claim partition 109 {2014-01-10 00:58:09,284} DEBUG [bill-generated-hadoop-consumer_tm1mwdpl04-1389222547995-29a6dce9_watcher_executor] (?:?) - initial fetch offset of bill-generated:11: fetched offset = 152: consumed offset = 152 is 152 {2014-01-10 00:58:09,284} DEBUG [catalina-exec-12-SendThread(tvip-m1-mw-zookeeper.dish.com:2181)] (ClientCnxn.java:839) - Reading reply sessionid:0x1437b2879870005, packet:: clientPath:null serverPath:null finished:false header:: 619,1 replyHeader:: 619,51539617508,0 request:: '/consumers/account-activated-hadoop-consumer/owners/account-activated/68,#6163636f756e742d6163746976617465642d6861646f6f702d636f6e73756d65725f746d316d7764706c30342d313338393232323535373930362d35363262363733382d30,v{s{31,s{'world,'anyone}}},1 response:: '/consumers/account-activated-hadoop-consumer/owners/account-activated/68 {2014-01-10 00:58:09,284} DEBUG [account-access-hadoop-consumer_tm1mwdpl04-1389222551916-a0c87abc_watcher_executor] (?:?) - [account-access-hadoop-consumer_tm1mwdpl04-1389222551916-a0c87abc], account-access:27: fetched offset = 9655: consumed offset = 9655 selected new offset 9655 {2014-01-10 00:58:09,284} INFO [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b_watcher_executor] (?:?) - [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b-leader-finder-thread], Shutdown completed {2014-01-10 00:58:09,284} INFO [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b-leader-finder-thread] (?:?) - [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b-leader-finder-thread], Stopped {2014-01-10 00:58:09,285} INFO [account-info-updated-hadoop-consumer_tm1mwdpl04-1389222553159-ad59660b_watcher_executor] (?:?) - [ConsumerFetcherManager-1389222553163] Stopping all fetchers
