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https://issues.apache.org/jira/browse/HBASE-13109?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14357703#comment-14357703
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Andrew Purtell commented on HBASE-13109:
----------------------------------------
The commit of this to 0.98 branch breaks Phoenix compilation if using
-Dhbase.version=0.98.12-SNAPSHOT (after installing latest 0.98 into the local
Maven cache):
{noformat}
[ERROR]
/Users/apurtell/src/phoenix/phoenix-core/src/main/java/org/apache/hadoop/hbase/regionserver/IndexHalfStoreFileReader.java:[141,35]
<anonymous org.apache.hadoop.hbase.regionserver.IndexHalfStoreFileReader$1> is
not abstract and does not override abstract method getNextIndexedKey() in
org.apache.hadoop.hbase.io.hfile.HFileScanner
[ERROR]
/Users/apurtell/src/phoenix/phoenix-core/src/main/java/org/apache/phoenix/hbase/index/scanner/FilteredKeyValueScanner.java:[37,8]
org.apache.phoenix.hbase.index.scanner.FilteredKeyValueScanner is not abstract
and does not override abstract method getNextIndexedKey() in
org.apache.hadoop.hbase.regionserver.KeyValueScanner
{noformat}
KeyValueScanner and HFileScanner are both marked as InterfaceAudience.Private.
What should we do here?
[~jamestaylor]
> 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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