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https://issues.apache.org/jira/browse/HBASE-13109?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14359047#comment-14359047
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James Taylor commented on HBASE-13109:
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Would it be possible to have base classes for these we can extend from to
shield us from interface additions?
The FilteredKeyValueScanner class is deep in the bowels of mutable secondary
indexing - [~jesse_yates] - any ideas for how to get this on to non
private/evolving interfaces?
The HFileScanner anonymous implementation is in the bowels of local indexes.
Same question, [~rajeshbabu] - any ideas for how to get this on to non
private/evolving interfaces?
> 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.
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