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https://issues.apache.org/jira/browse/KAFKA-13295?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17415195#comment-17415195
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Guozhang Wang commented on KAFKA-13295:
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As we talked about the potential fix in the near term, one possibility is that
`onPartitionAssigned` when new tasks are created, we always blindly do a
commitOffsetOrTransaction as well so that if there's any ongoing transactions,
it would be committed before we potentially go on to restore the newly assigned
tasks.
> Long restoration times for new tasks can lead to transaction timeouts
> ---------------------------------------------------------------------
>
> Key: KAFKA-13295
> URL: https://issues.apache.org/jira/browse/KAFKA-13295
> Project: Kafka
> Issue Type: Bug
> Components: streams
> Reporter: A. Sophie Blee-Goldman
> Priority: Critical
> Labels: eos
> Fix For: 3.1.0
>
>
> In some EOS applications with relatively long restoration times we've noticed
> a series of ProducerFencedExceptions occurring during/immediately after
> restoration. The broker logs were able to confirm these were due to
> transactions timing out.
> In Streams, it turns out we automatically begin a new txn when calling
> {{send}} (if there isn’t already one in flight). A {{send}} occurs often
> outside a commit during active processing (eg writing to the changelog),
> leaving the txn open until the next commit. And if a StreamThread has been
> actively processing when a rebalance results in a new stateful task without
> revoking any existing tasks, the thread won’t actually commit this open txn
> before it goes back into the restoration phase while it builds up state for
> the new task. So the in-flight transaction is left open during restoration,
> during which the StreamThread only consumes from the changelog without
> committing, leaving it vulnerable to timing out when restoration times exceed
> the configured transaction.timeout.ms for the producer client.
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