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https://issues.apache.org/jira/browse/CASSANDRA-8833?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14360030#comment-14360030
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Marcus Eriksson commented on CASSANDRA-8833:
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[~thobbs] do we have any statistics on how much we gain in real life by the
redistribution?
> Stop opening compaction results early
> -------------------------------------
>
> Key: CASSANDRA-8833
> URL: https://issues.apache.org/jira/browse/CASSANDRA-8833
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Marcus Eriksson
> Fix For: 2.1.4
>
>
> We should simplify the code base by not doing early opening of compaction
> results. It makes it very hard to reason about sstable life cycles since they
> can be in many different states, "opened early", "starts moved", "shadowed",
> "final", instead of as before, basically just one (tmp files are not really
> 'live' yet so I don't count those). The ref counting of shared resources
> between sstables in these different states is also hard to reason about. This
> has caused quite a few issues since we released 2.1
> I think it all boils down to a performance vs code complexity issue, is
> opening compaction results early really 'worth it' wrt the performance gain?
> The results in CASSANDRA-6916 sure look like the benefits are big enough, but
> the difference should not be as big for people on SSDs (which most people who
> care about latencies are)
> WDYT [~benedict] [~jbellis] [~iamaleksey] [~JoshuaMcKenzie]?
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