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https://issues.apache.org/jira/browse/HBASE-9751?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13793440#comment-13793440
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Vladimir Rodionov commented on HBASE-9751:
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8 threads on my 4core CPU:
Row size = 37 bytes (1 CF + 1 CQ)
MemStoreScanner (default) - 80M rows per sec
MemStoreScanner(readpoint in ctor) - 97.5M rows per sec.




> Excessive  readpoints checks in MemStoreScanner and StoreFileScanner
> --------------------------------------------------------------------
>
>                 Key: HBASE-9751
>                 URL: https://issues.apache.org/jira/browse/HBASE-9751
>             Project: HBase
>          Issue Type: Bug
>    Affects Versions: 0.98.0, 0.94.12, 0.96.0
>            Reporter: Vladimir Rodionov
>            Assignee: Lars Hofhansl
>         Attachments: 9751-0.94.txt, 9751-trunk.txt
>
>
> It seems that usage of skipKVsNewerThanReadpoint in StoreFileScanner can be 
> greatly reduced or even eliminated all together (HFiles are immutable and no 
> new KVs can be inserted after scanner instance is created). The same is true 
> for MemStoreScanner which checks readpoint on every next() and seek(). Each 
> readpoint check is ThreadLocal.get() and it is quite expensive.  



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