[
https://issues.apache.org/jira/browse/CASSANDRA-622?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13099614#comment-13099614
]
Jonathan Ellis commented on CASSANDRA-622:
------------------------------------------
bq. reserving space for each with a [AtomicInteger] first
For an example of something similar, look at how SlabAllocator.Region.allocate
uses this approach to reserve parts of a region for the ByteBuffers it
allocates.
> Improve commitlog performance
> -----------------------------
>
> Key: CASSANDRA-622
> URL: https://issues.apache.org/jira/browse/CASSANDRA-622
> Project: Cassandra
> Issue Type: Improvement
> Reporter: Jonathan Ellis
> Priority: Minor
> Labels: gsoc, gsoc2010
>
> Postgresql uses fixed-size commitlog files that it pre-allocates (filling
> with zeros) so "appending" to the log can use cheaper fsync-without-metadata
> (length changes is "metadata"). Then, when a commitlog is not needed, it
> "recycles" it by renaming it to a higher number. Commitlog entries have an
> increasing id, and if you come to an out-of-sequence (earlier) id, then you
> must have have reached the end of the commitlog and are reading from the
> "recycled" part.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
