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https://issues.apache.org/jira/browse/KAFKA-5611?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16098973#comment-16098973
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Jason Gustafson commented on KAFKA-5611:
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[~pskianis] You'd have to get pretty unlikely with the timing, but a wakeup
following rebalance completion could explain the issue. Prior to invoking the
partition assignor, we have a check to ensure that we have up-to-date metadata.
It is possible to get a wakeup when fetching new metadata and the code does not
appear clever enough at the moment to resume assignment on the next call to
{{poll()}}. I'll submit a patch to fix this and maybe we can see if it
addresses the problem.
> One or more consumers in a consumer-group stop consuming after rebalancing
> --------------------------------------------------------------------------
>
> Key: KAFKA-5611
> URL: https://issues.apache.org/jira/browse/KAFKA-5611
> Project: Kafka
> Issue Type: Bug
> Affects Versions: 0.10.2.0
> Reporter: Panos Skianis
> Attachments: bad-server-with-more-logging-1.tar.gz, kka02, Server 1,
> Server 2, Server 3
>
>
> Scenario:
> - 3 zookeepers, 4 Kafkas. 0.10.2.0, with 0.9.0 compatibility still on
> (other apps need it but the one mentioned below is already on kafka 0.10.2.0
> client).
> - 3 servers running 1 consumer each under the same consumer groupId.
> - Servers seem to be consuming messages happily but then there is a timeout
> to an external service that causes our app to restart the Kafka Consumer on
> one of the servers (this is by design). That causes rebalancing of the group
> and upon restart of one of the Consumers seem to "block".
> - Server 3 is where the problems occur.
> - Problem fixes itself either by restarting one of the 3 servers or cause
> the group to rebalance again by using the console consumer with the
> autocommit set to false and using the same group.
>
> Note:
> - Haven't managed to recreate it at will yet.
> - Mainly happens in production environment, often enough. Hence I do not
> have any logs with DEBUG/TRACE statements yet.
> - Extracts from log of each app server are attached. Also the log of the
> kafka that seems to be dealing with the related group and generations.
> - See COMMENT lines in the files for further info.
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