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https://issues.apache.org/jira/browse/HBASE-10118?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13844460#comment-13844460
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Sergey Shelukhin commented on HBASE-10118:
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Yeah there's no good justification either way... strange behavior of custom
TSes during compaction is currently a given, e.g. if you put custom TS=1,
delete TS=3, put TS=2 the result depends on compaction timing, if compaction
happens after delete 2nd put will survive potentially forever, and if it
happens after 2nd put it will be dropped.
+1 on configurable
> Major compact keeps deletes with future timestamps
> --------------------------------------------------
>
> Key: HBASE-10118
> URL: https://issues.apache.org/jira/browse/HBASE-10118
> Project: HBase
> Issue Type: Bug
> Components: Compaction, Deletes, regionserver
> Reporter: Max Lapan
> Priority: Minor
>
> Hello!
> During migration from HBase 0.90.6 to 0.94.6 we found changed behaviour in
> how major compact handles delete markers with timestamps in the future.
> Before HBASE-4721 major compact purged deletes regardless of their timestamp.
> Newer versions keep them in HFile until timestamp not reached.
> I guess this happened due to new check in ScanQueryMatcher
> {{EnvironmentEdgeManager.currentTimeMillis() - timestamp) <=
> timeToPurgeDeletes}}.
> This can be worked around by specifying large negative value in
> {{hbase.hstore.time.to.purge.deletes}} option, but, unfortunately, negative
> values are pulled up to zero by Math.max in HStore.java.
> Maybe, we are trying to do something weird by specifing delete timestamp in
> future, but HBASE-4721 definitely breaks old behaviour we rely on.
> Steps to reproduce this:
> {code}
> put 'test', 'delmeRow', 'delme:something', 'hello'
> flush 'test'
> delete 'test', 'delmeRow', 'delme:something', 1394161431061
> flush 'test'
> major_compact 'test'
> {code}
> Before major_compact we have two hfiles with the following:
> {code}
> first:
> K: delmeRow/delme:something/1384161431061/Put/vlen=5/ts=0
> second:
> K: delmeRow/delme:something/1394161431061/DeleteColumn/vlen=0/ts=0
> {code}
> After major compact we get the following:
> {code}
> K: delmeRow/delme:something/1394161431061/DeleteColumn/vlen=0/ts=0
> {code}
> In our installation, we resolved this by removing Math.max and setting
> hbase.hstore.time.to.purge.deletes to Integer.MIN_VALUE, which purges delete
> markers, and it looks like a solution. But, maybe, there are better approach.
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