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https://issues.apache.org/jira/browse/CASSANDRA-5371?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13609358#comment-13609358
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Jeremiah Jordan commented on CASSANDRA-5371:
--------------------------------------------

I could see this possibly helping if you left the non L0 alone and went to STCS 
for L0 until the write load stopped. But you have to come up with a heuristic 
to know when to shut off LCS.  So a cluster with a periodic write load, which 
was too high for LCS's increased IO needs, would revert to STCS of L0 only 
until the load dropped.  You would then have to play catchup shoving all that 
L0 data into the other levels. I could see use cases where this would be 
useful, such as periodic large data dumps into a cluster. You would have to be 
careful that there was enough down time between dumps for LCS to catchup.
                
> Perform size-tiered compactions in L0
> -------------------------------------
>
>                 Key: CASSANDRA-5371
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-5371
>             Project: Cassandra
>          Issue Type: Bug
>          Components: Core
>            Reporter: Jonathan Ellis
>            Assignee: T Jake Luciani
>             Fix For: 2.0
>
>
> If LCS gets behind, read performance deteriorates as we have to check bloom 
> filters on man sstables in L0.  For wide rows, this can mean having to seek 
> for each one since the BF doesn't help us reject much.
> Performing size-tiered compaction in L0 will mitigate this until we can catch 
> up on merging it into higher levels.

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