[
https://issues.apache.org/jira/browse/HDFS-3529?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Trevor Robinson updated HDFS-3529:
----------------------------------
Attachment: dfsio-x86-trunk-vs-3529.png
Attached image shows Ganglia charts from two runs of TestDFSIO (each with Write
followed by Read): first is with this patch, second is without it. The I/O
rates are essentially the same (disk-bound), but the write phase shows 5% lower
CPU utilization with the patch. CPU used is a Sandy Bridge E3-1240 (4 cores,
3.3 GHz).
> Use direct buffers for data in write path
> -----------------------------------------
>
> Key: HDFS-3529
> URL: https://issues.apache.org/jira/browse/HDFS-3529
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: data-node, performance
> Affects Versions: 2.0.0-alpha
> Reporter: Todd Lipcon
> Assignee: Trevor Robinson
> Attachments: dfsio-x86-trunk-vs-3529.png, HDFS-3529.patch
>
>
> The write path currently makes several unnecessary data copies in order to go
> to and from byte arrays. We can improve performance by using direct byte
> buffers to avoid the copy. This is also a prerequisite for native checksum
> calculation (HDFS-3528)
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
