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https://issues.apache.org/jira/browse/PHOENIX-1906?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14507420#comment-14507420
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Andrew Purtell commented on PHOENIX-1906:
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It's not quite as simple as "let's just add code to HBase", we are considering
it but there's some legwork outstanding:
https://issues.apache.org/jira/browse/HBASE-12790?focusedCommentId=14507418&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14507418
> With large number of guideposts, queries that iterate over a small range gets
> starved when running concurrently with larger queries
> -----------------------------------------------------------------------------------------------------------------------------------
>
> Key: PHOENIX-1906
> URL: https://issues.apache.org/jira/browse/PHOENIX-1906
> Project: Phoenix
> Issue Type: Bug
> Reporter: Mujtaba Chohan
>
> Consider the scenario with a single region server. Table has 500 guide posts
> (data is large enough that it won't fit either into HBase block or OS page
> cache so it gets blocked on disk I/O during scans) and running the following
> 2 queries concurrently with and without stats enabled:
> {code}select count(*) from table{code}
> {code}select * from table limit 10{code}
> With stats *disabled*, average time for these two queries is 100sec and 100ms
> respectively. However with stats long running count aggregate query time
> drops to 8 second but limit query time increases to 3 seconds. Degradation in
> limit query time is even more evident when concurrency level is further
> increased.
> [~jamestaylor]
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