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https://issues.apache.org/jira/browse/HBASE-16296?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15396750#comment-15396750
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James Taylor commented on HBASE-16296:
--------------------------------------
To setup, follow the directions in generatedata-snippet.java to create and
populate the table. Run the repro-snippet.java to demonstrate the issue:
- keep the {{hbase.client.scanner.caching}} at 5 and notice the long pause
before "Done" is printed.
- change {{hbase.client.scanner.caching}} to 7 and notice that there's no
longer a pause when the script executes.
Note that functionally, it works, but the performance severely degrades when
the {{hbase.client.scanner.caching}} value is equal to the number of rows in
the PageFilter.
FYI, [~lhofhansl].
> Reverse scan performance degrades when scanner cache size matches page filter
> size
> ----------------------------------------------------------------------------------
>
> Key: HBASE-16296
> URL: https://issues.apache.org/jira/browse/HBASE-16296
> Project: HBase
> Issue Type: Bug
> Reporter: James Taylor
> Attachments: generatedata-snippet.java, repro-snippet.java
>
>
> When a reverse scan is done, the server seems to not know it's done when the
> scanner cache size matches the number of rows in a PageFilter. See
> PHOENIX-3121 for how this manifests itself. We have a standalone, pure HBase
> API reproducer too that I'll attach (courtesy of [~churromorales] and
> [~mujtabachohan]).
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