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https://issues.apache.org/jira/browse/KAFKA-9177?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17369771#comment-17369771
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A. Sophie Blee-Goldman commented on KAFKA-9177:
-----------------------------------------------

[~apolyakov] this ticket was specifically about pausing those completed 
changelogs in the restore consumer's assignment so that it doesn't continue to 
fetch records beyond the "end" of the changelog. The log message you're seeing 
doesn't indicate that this wasn't done, it's just a debug message to confirm 
we've finished restoring all changelogs when we run through the no-op restore 
phase after restoration is complete.

I wouldn't worry about it.

 

> Pause completed partitions on restore consumer
> ----------------------------------------------
>
>                 Key: KAFKA-9177
>                 URL: https://issues.apache.org/jira/browse/KAFKA-9177
>             Project: Kafka
>          Issue Type: Improvement
>          Components: streams
>            Reporter: A. Sophie Blee-Goldman
>            Assignee: Guozhang Wang
>            Priority: Major
>             Fix For: 2.6.0
>
>
> The StoreChangelogReader is responsible for tracking and restoring active 
> tasks, but once a store has finished restoring it will continue polling for 
> records on that partition.
> Ordinarily this doesn't make a difference as a store is not completely 
> restored until its entire changelog has been read, so there are no more 
> records for poll to return anyway. But if the restoring state is actually an 
> optimized source KTable, the changelog is just the source topic and poll will 
> keep returning records for that partition until all stores have been restored.
> Note that this isn't a correctness issue since it's just the restore 
> consumer, but it is wasteful to be polling for records and throwing them 
> away. We should pause completed partitions in StoreChangelogReader so we 
> don't slow down the restore consumer in reading from the unfinished changelog 
> topics, and avoid wasted network.



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