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https://issues.apache.org/jira/browse/KAFKA-1305?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14363129#comment-14363129
]
Dmitry Bugaychenko commented on KAFKA-1305:
-------------------------------------------
Even with a fast dedicated channel there will be a race condition in switching
leadership. It could be removed either by complicating the protocol (eg. the
new leader shoul take leadership only after getting "not a leader" respone in
fetcher thread from the old one, while the old leader should stop handling
produce request allowing fetches only from the new leader untill it gets
everything), or, may be, it is worth to consider getting rid of controller in
partition leader election and use distributed elections in ZK.
> Controller can hang on controlled shutdown with auto leader balance enabled
> ---------------------------------------------------------------------------
>
> Key: KAFKA-1305
> URL: https://issues.apache.org/jira/browse/KAFKA-1305
> Project: Kafka
> Issue Type: Bug
> Reporter: Joel Koshy
> Assignee: Sriharsha Chintalapani
> Priority: Blocker
> Fix For: 0.8.2.0, 0.9.0
>
> Attachments: KAFKA-1305.patch, KAFKA-1305.patch,
> KAFKA-1305_2014-10-13_07:30:45.patch
>
>
> This is relatively easy to reproduce especially when doing a rolling bounce.
> What happened here is as follows:
> 1. The previous controller was bounced and broker 265 became the new
> controller.
> 2. I went on to do a controlled shutdown of broker 265 (the new controller).
> 3. In the mean time the automatically scheduled preferred replica leader
> election process started doing its thing and starts sending
> LeaderAndIsrRequests/UpdateMetadataRequests to itself (and other brokers).
> (t@113 below).
> 4. While that's happening, the controlled shutdown process on 265 succeeds
> and proceeds to deregister itself from ZooKeeper and shuts down the socket
> server.
> 5. (ReplicaStateMachine actually removes deregistered brokers from the
> controller channel manager's list of brokers to send requests to. However,
> that removal cannot take place (t@18 below) because preferred replica leader
> election task owns the controller lock.)
> 6. So the request thread to broker 265 gets into infinite retries.
> 7. The entire broker shutdown process is blocked on controller shutdown for
> the same reason (it needs to acquire the controller lock).
> Relevant portions from the thread-dump:
> "Controller-265-to-broker-265-send-thread" - Thread t@113
> java.lang.Thread.State: TIMED_WAITING
> at java.lang.Thread.sleep(Native Method)
> at
> kafka.controller.RequestSendThread$$anonfun$liftedTree1$1$1.apply$mcV$sp(ControllerChannelManager.scala:143)
> at kafka.utils.Utils$.swallow(Utils.scala:167)
> at kafka.utils.Logging$class.swallowWarn(Logging.scala:92)
> at kafka.utils.Utils$.swallowWarn(Utils.scala:46)
> at kafka.utils.Logging$class.swallow(Logging.scala:94)
> at kafka.utils.Utils$.swallow(Utils.scala:46)
> at
> kafka.controller.RequestSendThread.liftedTree1$1(ControllerChannelManager.scala:143)
> at
> kafka.controller.RequestSendThread.doWork(ControllerChannelManager.scala:131)
> - locked java.lang.Object@6dbf14a7
> at kafka.utils.ShutdownableThread.run(ShutdownableThread.scala:51)
> Locked ownable synchronizers:
> - None
> ...
> "Thread-4" - Thread t@17
> java.lang.Thread.State: WAITING on
> java.util.concurrent.locks.ReentrantLock$NonfairSync@4836840 owned by:
> kafka-scheduler-0
> at sun.misc.Unsafe.park(Native Method)
> at java.util.concurrent.locks.LockSupport.park(LockSupport.java:156)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:811)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:842)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1178)
> at
> java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLock.java:186)
> at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:262)
> at kafka.utils.Utils$.inLock(Utils.scala:536)
> at kafka.controller.KafkaController.shutdown(KafkaController.scala:642)
> at
> kafka.server.KafkaServer$$anonfun$shutdown$9.apply$mcV$sp(KafkaServer.scala:242)
> at kafka.utils.Utils$.swallow(Utils.scala:167)
> at kafka.utils.Logging$class.swallowWarn(Logging.scala:92)
> at kafka.utils.Utils$.swallowWarn(Utils.scala:46)
> at kafka.utils.Logging$class.swallow(Logging.scala:94)
> at kafka.utils.Utils$.swallow(Utils.scala:46)
> at kafka.server.KafkaServer.shutdown(KafkaServer.scala:242)
> at
> kafka.server.KafkaServerStartable.shutdown(KafkaServerStartable.scala:46)
> at kafka.Kafka$$anon$1.run(Kafka.scala:42)
> ...
> "kafka-scheduler-0" - Thread t@117
> java.lang.Thread.State: WAITING on
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject@1dc407fc
> at sun.misc.Unsafe.park(Native Method)
> at java.util.concurrent.locks.LockSupport.park(LockSupport.java:156)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1987)
> at
> java.util.concurrent.LinkedBlockingQueue.put(LinkedBlockingQueue.java:306)
> at
> kafka.controller.ControllerChannelManager.sendRequest(ControllerChannelManager.scala:57)
> - locked java.lang.Object@578b748f
> at
> kafka.controller.KafkaController.sendRequest(KafkaController.scala:657)
> at
> kafka.controller.ControllerBrokerRequestBatch$$anonfun$sendRequestsToBrokers$2.apply(ControllerChannelManager.scala:290)
> at
> kafka.controller.ControllerBrokerRequestBatch$$anonfun$sendRequestsToBrokers$2.apply(ControllerChannelManager.scala:282)
> at
> scala.collection.mutable.HashMap$$anonfun$foreach$1.apply(HashMap.scala:80)
> at
> scala.collection.mutable.HashMap$$anonfun$foreach$1.apply(HashMap.scala:80)
> at scala.collection.Iterator$class.foreach(Iterator.scala:631)
> at
> scala.collection.mutable.HashTable$$anon$1.foreach(HashTable.scala:161)
> at
> scala.collection.mutable.HashTable$class.foreachEntry(HashTable.scala:194)
> at scala.collection.mutable.HashMap.foreachEntry(HashMap.scala:39)
> at scala.collection.mutable.HashMap.foreach(HashMap.scala:80)
> at
> kafka.controller.ControllerBrokerRequestBatch.sendRequestsToBrokers(ControllerChannelManager.scala:282)
> at
> kafka.controller.PartitionStateMachine.handleStateChanges(PartitionStateMachine.scala:126)
> at
> kafka.controller.KafkaController.onPreferredReplicaElection(KafkaController.scala:612)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4$$anonfun$apply$17$$anonfun$apply$5.apply$mcV$sp(KafkaController.scala:1119)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4$$anonfun$apply$17$$anonfun$apply$5.apply(KafkaController.scala:1114)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4$$anonfun$apply$17$$anonfun$apply$5.apply(KafkaController.scala:1114)
> at kafka.utils.Utils$.inLock(Utils.scala:538)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4$$anonfun$apply$17.apply(KafkaController.scala:1111)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4$$anonfun$apply$17.apply(KafkaController.scala:1109)
> at
> scala.collection.mutable.HashMap$$anonfun$foreach$1.apply(HashMap.scala:80)
> at
> scala.collection.mutable.HashMap$$anonfun$foreach$1.apply(HashMap.scala:80)
> at scala.collection.Iterator$class.foreach(Iterator.scala:631)
> at
> scala.collection.mutable.HashTable$$anon$1.foreach(HashTable.scala:161)
> at
> scala.collection.mutable.HashTable$class.foreachEntry(HashTable.scala:194)
> at scala.collection.mutable.HashMap.foreachEntry(HashMap.scala:39)
> at scala.collection.mutable.HashMap.foreach(HashMap.scala:80)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4.apply(KafkaController.scala:1109)
> at
> kafka.controller.KafkaController$$anonfun$kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance$4.apply(KafkaController.scala:1088)
> at
> scala.collection.immutable.HashMap$HashMap1.foreach(HashMap.scala:125)
> at
> scala.collection.immutable.HashMap$HashTrieMap.foreach(HashMap.scala:344)
> at
> kafka.controller.KafkaController.kafka$controller$KafkaController$$checkAndTriggerPartitionRebalance(KafkaController.scala:1088)
> at
> kafka.controller.KafkaController$$anonfun$onControllerFailover$1.apply$mcV$sp(KafkaController.scala:323)
> at kafka.utils.KafkaScheduler$$anon$1.run(KafkaScheduler.scala:100)
> at
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
> at
> java.util.concurrent.FutureTask$Sync.innerRunAndReset(FutureTask.java:317)
> at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:150)
> at
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$101(ScheduledThreadPoolExecutor.java:98)
> at
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.runPeriodic(ScheduledThreadPoolExecutor.java:180)
> at
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:204)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
> at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
> at java.lang.Thread.run(Thread.java:662)
> Locked ownable synchronizers:
> - locked java.util.concurrent.locks.ReentrantLock$NonfairSync@4836840
> - locked java.util.concurrent.locks.ReentrantLock$NonfairSync@4918530
> ...
> "ZkClient-EventThread-18-/kafka-shadow" - Thread t@18
> java.lang.Thread.State: WAITING on
> java.util.concurrent.locks.ReentrantLock$NonfairSync@4836840 owned by:
> kafka-scheduler-0
> at sun.misc.Unsafe.park(Native Method)
> at java.util.concurrent.locks.LockSupport.park(LockSupport.java:156)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:811)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireQueued(AbstractQueuedSynchronizer.java:842)
> at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquire(AbstractQueuedSynchronizer.java:1178)
> at
> java.util.concurrent.locks.ReentrantLock$NonfairSync.lock(ReentrantLock.java:186)
> at java.util.concurrent.locks.ReentrantLock.lock(ReentrantLock.java:262)
> at kafka.utils.Utils$.inLock(Utils.scala:536)
> at
> kafka.controller.ReplicaStateMachine$BrokerChangeListener.handleChildChange(ReplicaStateMachine.scala:328)
> at org.I0Itec.zkclient.ZkClient$7.run(ZkClient.java:568)
> at org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:71)
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