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https://issues.apache.org/jira/browse/CASSANDRA-3950?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13214630#comment-13214630
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Pavel Yaskevich commented on CASSANDRA-3950:
--------------------------------------------
The problems with your patch:
# you use bytesSinceCacheFlush instead of bytesSinceTrickleFsync in
flushInternal() method.
# trickleFsyncByteInterval should be bumped by 1024 * 1024 in the SW
constructor to make it bytes because bytesSinceTrickleFsync is counted in bytes
granularity.
> support trickling fsync() on writes
> -----------------------------------
>
> Key: CASSANDRA-3950
> URL: https://issues.apache.org/jira/browse/CASSANDRA-3950
> Project: Cassandra
> Issue Type: Improvement
> Components: Core
> Reporter: Peter Schuller
> Assignee: Peter Schuller
> Fix For: 1.1.0
>
> Attachments: CASSANDRA-3950-1.1.txt
>
>
> Attaching a patch to support fsync():ing every N megabytes of data written
> using sequential writers. The motivation is to avoid the kernel flushing out
> pages in bulk.
> It makes sense for both platters and SSD:s, but it's particularly good for
> SSD:s because the negative consequences of fsync():ing more often are much
> more limited than with platters, and the *need* is to some extent greater
> because of the fact that with SSD:s you're much more likely to be e.g.
> streaming data quickly or compacting quickly, since you're not having to
> throttle everything as extremely as with platters, and you easily write fast
> enough for this to be a problem if you're targetting good latency at the
> outliers.
> I'm nominating it for 1.1.0 because, if disabled, the probability of this
> being a regression seems very low.
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