cassandra-commits mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Marcus Eriksson (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (CASSANDRA-11106) Experiment with strategies for picking compaction candidates in LCS
Date Sat, 26 Mar 2016 07:59:25 GMT

    [ https://issues.apache.org/jira/browse/CASSANDRA-11106?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15212872#comment-15212872
] 

Marcus Eriksson commented on CASSANDRA-11106:
---------------------------------------------

[~dikanggu] no, feel free to take it!

> Experiment with strategies for picking compaction candidates in LCS
> -------------------------------------------------------------------
>
>                 Key: CASSANDRA-11106
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-11106
>             Project: Cassandra
>          Issue Type: Improvement
>            Reporter: Marcus Eriksson
>              Labels: lcs
>             Fix For: 3.x
>
>
> Ideas taken here: http://rocksdb.org/blog/2921/compaction_pri/
> Current strategy in LCS is that we keep track of the token that was last compacted and
then we start a compaction with the sstable containing the next token (kOldestSmallestSeqFirst
in the blog post above)
> The rocksdb blog post above introduces a few ideas how this could be improved:
> * pick the 'coldest' sstable (sstable with the oldest max timestamp) - we want to keep
the hot data (recently updated) in the lower levels to avoid write amplification
> * pick the sstable with the highest tombstone ratio, we want to get tombstones to the
top level as quickly as possible.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message