[ 
https://issues.apache.org/jira/browse/HBASE-13109?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14362609#comment-14362609
 ] 

Lars Hofhansl commented on HBASE-13109:
---------------------------------------

[~giacomotaylor], what do you think? If we delay to 0.98.13, I think we can 
have new versions of Phoenix by then.
(If not, might as well leave it in 0.98.12)

We should also check a version Phoenix built against t

> Make better SEEK vs SKIP decisions during scanning
> --------------------------------------------------
>
>                 Key: HBASE-13109
>                 URL: https://issues.apache.org/jira/browse/HBASE-13109
>             Project: HBase
>          Issue Type: Improvement
>            Reporter: Lars Hofhansl
>            Assignee: Lars Hofhansl
>             Fix For: 2.0.0, 1.0.1, 1.1.0, 0.98.12
>
>         Attachments: 13109-0.98-v4.txt, 13109-trunk-v2.txt, 
> 13109-trunk-v3.txt, 13109-trunk-v4.txt, 13109-trunk-v5.txt, 13109-trunk.txt, 
> nextIndexKVChange_new.patch
>
>
> I'm re-purposing this issue to add a heuristic as to when to SEEK and when to 
> SKIP Cells. This has come up in various issues, and I think I have a way to 
> finally fix this now. HBASE-9778, HBASE-12311, and friends are related.
> --- Old description ---
> This is a continuation of HBASE-9778.
> We've seen a scenario of a very slow scan over a region using a timerange 
> that happens to fall after the ts of any Cell in the region.
> Turns out we spend a lot of time seeking.
> Tested with a 5 column table, and the scan is 5x faster when the timerange 
> falls before all Cells' ts.
> We can use the lookahead hint introduced in HBASE-9778 to do opportunistic 
> SKIPing before we actually seek.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to