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https://issues.apache.org/jira/browse/KAFKA-8522?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16919669#comment-16919669
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Jun Rao commented on KAFKA-8522:
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[~Yohan123], not sure that I fully understood your question. We need to write
the partition level checkpoint after the cleaning of each log. Typically, the
latter takes much more time than the former. So the overhead of the former
should be small?
Also, if we are adding a new checkpoint file, we probably want to create a KIP
to discuss this a bit more.
> Tombstones can survive forever
> ------------------------------
>
> Key: KAFKA-8522
> URL: https://issues.apache.org/jira/browse/KAFKA-8522
> Project: Kafka
> Issue Type: Improvement
> Components: log cleaner
> Reporter: Evelyn Bayes
> Priority: Minor
>
> This is a bit grey zone as to whether it's a "bug" but it is certainly
> unintended behaviour.
>
> Under specific conditions tombstones effectively survive forever:
> * Small amount of throughput;
> * min.cleanable.dirty.ratio near or at 0; and
> * Other parameters at default.
> What happens is all the data continuously gets cycled into the oldest
> segment. Old records get compacted away, but the new records continuously
> update the timestamp of the oldest segment reseting the countdown for
> deleting tombstones.
> So tombstones build up in the oldest segment forever.
>
> While you could "fix" this by reducing the segment size, this can be
> undesirable as a sudden change in throughput could cause a dangerous number
> of segments to be created.
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