java - 重新启动无异常关闭的 Kafka Streams 应用程序

Question

我正在使用 Kafka Streams v. 0.10.2.0 通过简单的处理在主题之间进行流式传输。最近，我遇到了一个问题，其中一个经纪人宕机了，kafka 流应用程序关闭并保持关闭状态，直到我手动重新启动它。尝试调试此问题时，我无法从日志中了解到底是什么导致了此问题，以下是日志摘录:

INFO [StreamThread-1] o.a.k.c.c.i.ConsumerCoordinator - Revoking previously assigned partitions [topicname-3, topicname-1, topicname-2] for group streams-group
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] partitions [[topicname-3, topicname-1, topicname-2]] revoked at the beginning of consumer rebalance.
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task's topology 0_1
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task's topology 0_2
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task's topology 0_3
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_1
INFO [kafka-coordinator-heartbeat-thread | streams-group] o.a.k.c.c.i.AbstractCoordinator - Marking the coordinator 127.0.0.1:9092 dead for group streams-group
INFO [kafka-coordinator-heartbeat-thread | streams-group] o.a.k.c.c.i.AbstractCoordinator - Discovered coordinator 127.0.0.1:9092 for group streams-group.
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_2
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_3
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Committing consumer offsets of task 0_1
ERROR [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Failed while executing StreamTask 0_1 due to commit consumer offsets: 
org.apache.kafka.clients.consumer.CommitFailedException: Commit cannot be completed since the group has already rebalanced and assigned the partitions to another member. This means that the time between subsequent calls to poll() was longer than the configured max.poll.interval.ms, which typically implies that the poll loop is spending too much time message processing. You can address this either by increasing the session timeout or by reducing the maximum size of batches returned in poll() with max.poll.records.
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Updating suspended tasks to contain active tasks [[0_1, 0_2, 0_3]]
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Removing all active tasks [[0_1, 0_2, 0_3]]
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Removing all standby tasks [[]]
ERROR [StreamThread-1] o.a.k.c.c.i.ConsumerCoordinator - User provided listener org.apache.kafka.streams.processor.internals.StreamThread$1 for group streams-group failed on partition revocation
INFO [StreamThread-1] o.a.k.c.c.i.AbstractCoordinator - (Re-)joining group streams-group
INFO [StreamThread-1] o.a.k.c.c.i.AbstractCoordinator - Marking the coordinator dead for group streams-group
INFO [StreamThread-1] o.a.k.c.c.i.AbstractCoordinator - Discovered coordinator for group streams-group.
INFO [StreamThread-1] o.a.k.c.c.i.AbstractCoordinator - (Re-)joining group streams-group
INFO [StreamThread-1] o.a.k.s.p.i.StreamPartitionAssignor - stream-thread [StreamThread-1] Constructed client metadata ...
INFO [StreamThread-1] o.a.k.s.p.i.StreamPartitionAssignor - stream-thread [StreamThread-1] Completed validating internal topics in partition assignor
INFO [StreamThread-1] o.a.k.s.p.i.StreamPartitionAssignor - stream-thread [StreamThread-1] Completed validating internal topics in partition assignor
INFO [StreamThread-1] o.a.k.s.p.i.StreamPartitionAssignor - stream-thread [StreamThread-1] Assigned tasks to clients as {...=[activeTasks: ([0_0, 0_4]) assignedTasks: ([0_0, 0_4]) prevActiveTasks: ([]) prevAssignedTasks: ([]) capacity: 1.0 cost: 0.2], ...=[activeTasks: ([0_1, 0_2, 0_3]) assignedTasks: ([0_1, 0_2, 0_3]) prevActiveTasks: ([]) prevAssignedTasks: ([]) capacity: 1.0 cost: 0.30000000000000004]}.
INFO [StreamThread-1] o.a.k.c.c.i.AbstractCoordinator - Successfully joined group streams-group with generation 17
INFO [StreamThread-1] o.a.k.c.c.i.ConsumerCoordinator - Setting newly assigned partitions [topicname-3, topicname-1, topicname-2] for group streams-group
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] New partitions [[topicname-3, topicname-1, topicname-2]] assigned at the end of consumer rebalance.
INFO [StreamThread-1] o.a.k.s.p.i.StreamTask - task [0_1] Initializing processor nodes of the topology
INFO [StreamThread-1] o.a.k.s.p.i.StreamTask - task [0_2] Initializing processor nodes of the topology
INFO [StreamThread-1] o.a.k.s.p.i.StreamTask - task [0_3] Initializing processor nodes of the topology
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Shutting down
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task 0_1
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task 0_2
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing a task 0_3
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_1
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_2
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Flushing state stores of task 0_3
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing the state manager of task 0_1
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing the state manager of task 0_2
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Closing the state manager of task 0_3
INFO [StreamThread-1] o.a.k.c.p.KafkaProducer - Closing the Kafka producer with timeoutMillis = 9223372036854775807 ms.
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Removing all active tasks [[0_1, 0_2, 0_3]]
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Removing all standby tasks [[]]
INFO [StreamThread-1] o.a.k.s.p.i.StreamThread - stream-thread [StreamThread-1] Stream thread shutdown complete
WARN [StreamThread-1] o.a.k.s.p.i.StreamThread - Unexpected state transition from RUNNING to NOT_RUNNING

首先，处理花费很长时间似乎不太可能，因为它非常简单，并且应用程序运行了几个月，日志中没有类似的消息。

另外，从日志来看，kafka 流成功重新加入了组，但突然它就毫无异常(exception)地关闭了。我有两个流应用程序在不同的计算机上运行，​​并且在代理重新启动时同时关闭。

如何调试这个问题？它至少不应该抛出异常吗？另一个问题是，当流线程关闭时，应用程序的其余部分工作正常，因此它不会自动重新启动。我可以以某种方式捕获它并重新启动线程吗？保留策略使得消费者非常不希望陷入困境，我怎样才能使 kafka Streams 应用程序更可靠？

谢谢!

Answer 1

从日志中很难说。也许调试日志会揭示更多信息......

唯一的“盲目猜测”可能是，初始化拓扑的处理器节点期间出现错误。但如果有异常，实际上应该在日志中。这也可能是库中的错误。

关于监控您的应用程序，您有多种选择:

• 您可以注册一个 KafkaStreams#setUncaughtExceptionHandler() 来查看如果 StreamThread 是否会引发异常，从而导致线程死亡
• 您可以注册一个 KafkaStreams#setStateListener() 来查看应用是否进入 NOT_RUNNING 状态(顺便说一句:NOT_RUNNING 有一个已知问题0.10.2 和 0.11.0 中的 code> 状态 - 刚刚在 trunk 中修复:如果所有线程都已死亡，状态可能仍为 RUNNING，因此您应该监控仍在手动运行的线程数)

顺便说一句:我建议升级到包含多个重要错误修复的 0.10.2.1。