[
https://issues.apache.org/jira/browse/CASSANDRA-7994?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Oleg Anastasyev updated CASSANDRA-7994:
---------------------------------------
Attachment: CompressedCommitLogs-7994.txt
attached patch rebased on current 2.0 codebase
> 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
> 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)
