[
https://issues.apache.org/jira/browse/CASSANDRA-7994?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14379498#comment-14379498
]
Aleksey Yeschenko commented on CASSANDRA-7994:
----------------------------------------------
Since changing something as major as that on 2.0, or even 2.1 at the time was a
no go, we went with CASSANDRA-6809 on trunk option.
I believe that some of the points raised by Oleg have been addressed there,
though not all.
I suggest we create separate follow up tickets for the remained of them (like
we did with CASSANDRA-8634), to be addressed in either 3.0 or 3.1, if you can
find some time for that, Oleg.
Will be closing this one as a duplicate for now.
> Commit logs on the fly compression
> -----------------------------------
>
> Key: CASSANDRA-7994
> URL: https://issues.apache.org/jira/browse/CASSANDRA-7994
> Project: Cassandra
> Issue Type: New Feature
> Reporter: Oleg Anastasyev
> Assignee: Oleg Anastasyev
> Attachments: CompressedCommitLogs-7994.txt
>
>
> This patch employs lz4 algo to comress commit logs. This could be useful to
> conserve disk space either archiving commit logs for a long time or for
> conserviing iops for use cases with often and large mutations updating the
> same record.
> The compression is performed on blocks of 64k, for better cross mutation
> compression. CRC is computed on each 64k block, unlike original code
> computing it on each individual mutation.
> On one of our real production cluster this saved 2/3 of the space consumed by
> commit logs. The replay is 20-30% slower for the same number of mutations.
> While doing this, also refactored commit log reading code to CommitLogReader
> class, which i believe makes code cleaner.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
