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https://issues.apache.org/jira/browse/HBASE-14460?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14902943#comment-14902943
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stack commented on HBASE-14460:
-------------------------------

I thought this a little ugly because row could be massive... Maybe it'd be 
ok... row should stick around a short time only. Could try and get away with 
not making a copy.

> [Perf Regression] Merge of MVCC and SequenceId (HBASE-HBASE-8763) slowed 
> Increments, CheckAndPuts, batch operations
> -------------------------------------------------------------------------------------------------------------------
>
>                 Key: HBASE-14460
>                 URL: https://issues.apache.org/jira/browse/HBASE-14460
>             Project: HBase
>          Issue Type: Bug
>          Components: Performance
>            Reporter: stack
>            Assignee: stack
>            Priority: Critical
>         Attachments: 14460.txt, region_lock.png
>
>
> As reported by 鈴木俊裕 up on the mailing list -- see "Performance degradation 
> between CDH5.3.1(HBase0.98.6) and CDH5.4.5(HBase1.0.0)" -- our unification of 
> sequenceid and MVCC slows Increments (and other ops) as the mvcc needs to 
> 'catch up' to our current point before we can read the last Increment value 
> that we need to update.
> We can say that our Increment is just done wrong, we should just be writing 
> Increments and summing on read, but checkAndPut as well as batching 
> operations have the same issue. Fix.



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