[
https://issues.apache.org/jira/browse/CASSANDRA-5371?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13621653#comment-13621653
]
T Jake Luciani commented on CASSANDRA-5371:
-------------------------------------------
Oh good, this is what I wanted the implementation to end up being.
In LeveledManifest.getCompactionCandidates:
I think there is a bug in the size tier candidate checks. You seem to be size
tiering across all the non-compacting sstables and not the level0 ones. I
think you mean't to intersect the level0 sstables with the non-compacting ones.
You should also add a check after that to make sure the non-compacting level0
sstables are still > MAX_COMPACTING_L0
Also, the code only checks for STCS when a higher level is ready to be
compacted. Maybe move this to the top before the higher level checks. We know
the higher levels are seek bounded but the code should try to keep up with
level 0 flushes as much as possible.
> 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: Jonathan Ellis
> Fix For: 2.0
>
> Attachments: HybridCompactionStrategy.java
>
>
> 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.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
