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https://issues.apache.org/jira/browse/KAFKA-7697?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16834581#comment-16834581
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Rajini Sivaram commented on KAFKA-7697:
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[~yanrui] Thanks for the thread dumps. It looks like kafka_jstack.txt was using
an older release (not 2.1.1, perhaps 2.1.0 or earlier) since it doesn't seem to
have the fix for this Jira. Can you confirm that?
322.dump shows the issue described in KAFKA-8151 for 2.1.1 due to ZK session
expiry. As a workaround, you can increase ZK session timeouts for the broker
until KAFKA-8151 is fixed if you are regularly running into this issue. It will
be good to know if you see the issue with 2.2.0 if you are able to recreate.
Thanks.
> Possible deadlock in kafka.cluster.Partition
> --------------------------------------------
>
> Key: KAFKA-7697
> URL: https://issues.apache.org/jira/browse/KAFKA-7697
> Project: Kafka
> Issue Type: Bug
> Affects Versions: 2.1.0
> Reporter: Gian Merlino
> Assignee: Rajini Sivaram
> Priority: Blocker
> Fix For: 2.2.0, 2.1.1
>
> Attachments: 322.tdump, kafka.log, kafka_jstack.txt, threaddump.txt
>
>
> After upgrading a fairly busy broker from 0.10.2.0 to 2.1.0, it locked up
> within a few minutes (by "locked up" I mean that all request handler threads
> were busy, and other brokers reported that they couldn't communicate with
> it). I restarted it a few times and it did the same thing each time. After
> downgrading to 0.10.2.0, the broker was stable. I attached a thread dump from
> the last attempt on 2.1.0 that shows lots of kafka-request-handler- threads
> trying to acquire the leaderIsrUpdateLock lock in kafka.cluster.Partition.
> It jumps out that there are two threads that already have some read lock
> (can't tell which one) and are trying to acquire a second one (on two
> different read locks: 0x0000000708184b88 and 0x000000070821f188):
> kafka-request-handler-1 and kafka-request-handler-4. Both are handling a
> produce request, and in the process of doing so, are calling
> Partition.fetchOffsetSnapshot while trying to complete a DelayedFetch. At the
> same time, both of those locks have writers from other threads waiting on
> them (kafka-request-handler-2 and kafka-scheduler-6). Neither of those locks
> appear to have writers that hold them (if only because no threads in the dump
> are deep enough in inWriteLock to indicate that).
> ReentrantReadWriteLock in nonfair mode prioritizes waiting writers over
> readers. Is it possible that kafka-request-handler-1 and
> kafka-request-handler-4 are each trying to read-lock the partition that is
> currently locked by the other one, and they're both parked waiting for
> kafka-request-handler-2 and kafka-scheduler-6 to get write locks, which they
> never will, because the former two threads own read locks and aren't giving
> them up?
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