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https://issues.apache.org/jira/browse/KAFKA-19853?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18035535#comment-18035535
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Lucas Brutschy commented on KAFKA-19853:
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Yes. As colt says, it's just about the time when the stream thread is blocked,
and there is no processing in that timeframe. I think committing would help.
But for me the root cause is the write stall. If we have a transaction timeout
of 10s and writing to rocks DB takes 20s, we are in trouble.
Would kip-1035 resolve the write stalls?
> StreamThread blocks on StateUpdater during onAssignment()
> ---------------------------------------------------------
>
> Key: KAFKA-19853
> URL: https://issues.apache.org/jira/browse/KAFKA-19853
> Project: Kafka
> Issue Type: Bug
> Components: streams
> Affects Versions: 3.9.0
> Reporter: Colt McNealy
> Priority: Major
> Attachments: image (3).png, image (4).png, image (5).png
>
>
> We've observed that the `StreamThread` blocks waiting for a `Future` from the
> `StateUpdater` in the `StreamsPartitionAssigner#onAssignment()` method when
> we are moving a task out of the `StateUpdater` and onto the `StreamThread`.
>
> This can cause problems because, during restoration or with warmup replicas,
> the `StateUpdater#runOnce()` method can take a long time (upwards of 20
> seconds) when RocksDB stalls writes to allow compaction to keep up. In EOS
> this blockage may cause the transaction to time out, which is a big mess.
> This is because the `StreamThread` may have an open transaction before the
> `StreamsPartitionAssignor#onAssignment()` method is called.
>
> Some screenshots from the JFR below (credit to [~eduwerc]).
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