[
https://issues.apache.org/jira/browse/HDFS-3751?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13426937#comment-13426937
]
Colin Patrick McCabe commented on HDFS-3751:
--------------------------------------------
seems like a very good idea. Another good use for the monotonic timer.
> DN should log warnings for lengthy disk IOs
> -------------------------------------------
>
> Key: HDFS-3751
> URL: https://issues.apache.org/jira/browse/HDFS-3751
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: data-node
> Affects Versions: 1.2.0, 2.1.0-alpha
> Reporter: Todd Lipcon
> Assignee: Todd Lipcon
>
> Occasionally failing disks or other OS-and-below issues cause a single IO to
> take tens of seconds, or even minutes in the case of failures. This often
> results in timeout exceptions at the client side which are hard to diagnose.
> It would be easier to root-cause these issues if the DN logged a WARN like
> "IO of 64kb to volume /data/1/dfs/dn for block 12345234 client 1.2.3.4 took
> 61.3 seconds" or somesuch.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
