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https://issues.apache.org/jira/browse/PHOENIX-6207?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17236022#comment-17236022
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Kadir OZDEMIR commented on PHOENIX-6207:
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[~comnetwork], That is a good question. I noticed the HBase region server RPC
service does some caching of results returned by region scanners. So, within a
single RPC call, there will be more than one region scanner next operation.
This was one reason I used 1 second page size (i.e., 1 second next operation
time). Another reason is that I want to make Phoenix more responsive. Holding
resources in seconds is not good in general I think. I believe releasing
resources (threads, rpc handlers, memory, etc) rather quickly will improve in
general the availability and performance of the cluster. Maybe the default for
ungrouped operations should be different from grouped ones. I need to look
into this more. I do not know the right answer now. I think we can increase the
value into multiple seconds. Please note that this is not a hard limit. In
other words, if the processing a row takes multiple seconds, the next operation
will take multiple seconds even if we set the page size to 1 second.
Meanwhile, I am trying to run the precheckin tests for the master branch patch
and it is getting aborted without reporting the test results
(https://ci-hadoop.apache.org/job/PreCommit-PHOENIX-Build/210/consoleFull). Do
you know why?
> Paged server side grouped aggregate operations
> ----------------------------------------------
>
> Key: PHOENIX-6207
> URL: https://issues.apache.org/jira/browse/PHOENIX-6207
> Project: Phoenix
> Issue Type: Improvement
> Affects Versions: 5.0.0, 4.14.3
> Reporter: Kadir OZDEMIR
> Assignee: Kadir OZDEMIR
> Priority: Major
> Fix For: 4.16.0
>
> Attachments: PHOENIX-6207.4.x.001.patch, PHOENIX-6207.4.x.002.patch,
> PHOENIX-6207.4.x.003.patch, PHOENIX-6207.4.x.004.patch,
> PHOENIX-6207.4.x.005.patch, PHOENIX-6207.4.x.006.patch,
> PHOENIX-6207.master.001.patch, PHOENIX-6207.master.002.patch
>
>
> Phoenix provides the option of performing query operations on the client or
> server side. This is decided by the Phoenix optimizer based on configuration
> parameters. For the server side option, the table operation is parallelized
> such that multiple table regions are scanned. However, currently there is no
> paging capability and the server side operation can take long enough lead to
> HBase client timeouts. Putting a limit on the processing time within a single
> RPC call (i.e., the next operation time on the aggregate scanner) on the
> server side using a Phoenix level paging is highly desirable. A similar
> paging mechanism has been already implemented for index rebuild and
> verification operations and proven to be effective to prevent timeouts. This
> Jira is for implementing this paging for the server side grouped aggregate
> operations.
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