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https://issues.apache.org/jira/browse/CASSANDRA-8833?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14352991#comment-14352991
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Benedict commented on CASSANDRA-8833:
-------------------------------------

bq. run the exact same test 

that works too; should give a reasonable idea of ballpark effect on current 
state

> 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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