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https://issues.apache.org/jira/browse/HBASE-24742?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17157895#comment-17157895
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Lars Hofhansl commented on HBASE-24742:
---------------------------------------

Upon second thought. Perhaps a seek (not a reseek, but a seek that could 
actually goes backwards) could make it so that previousIndexedKey and 
nextIndexedKey are accidentally the same and we *still* would have to do the 
compare.

In my test the majority of the improvement came from the first change.


> Improve performance of SKIP vs SEEK logic
> -----------------------------------------
>
>                 Key: HBASE-24742
>                 URL: https://issues.apache.org/jira/browse/HBASE-24742
>             Project: HBase
>          Issue Type: Bug
>          Components: Performance, regionserver
>    Affects Versions: 3.0.0-alpha-1, 1.7.0, 2.4.0
>            Reporter: Lars Hofhansl
>            Assignee: Lars Hofhansl
>            Priority: Major
>         Attachments: hbase-1.6-regression-flame-graph.png, 
> hbase-24742-branch-1.txt
>
>
> In our testing of HBase 1.3 against the current tip of branch-1 we saw a 30% 
> slowdown in scanning scenarios.
> We tracked it back to HBASE-17958 and HBASE-19863.
> Both add comparisons to one of the tightest HBase has.
> [~bharathv]



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