[CentOS] I/O size distribution?

Wed Dec 22 00:54:19 UTC 2010
Jeff Layton <laytonjb at att.net>

  On 12/21/2010 05:01 PM, Antonello Piemonte wrote:
> Hello
>
> I have read that under Solaris one can use DTrace to get I/O request
> size distribution on a global scale (also on a per process/pid basis).
> See for example
>
> http://prefetch.net/articles/observeiodtk.html
>
> Can anyone recommend an alternative to get similar information under
> CentOS? I looked into dtrace for linux but it seems still work in
> progress, even putting aside CDDL issues ...
>

If you want to look at the specific run of an application and
not the system as a whole or on a continual basis, then you
can use strace.

However, this can produce a great deal of data. So I wrote a
simple tool to scan through the strace output file and produce
some statistics. You can download it at:

http://clusterbuffer.wetpaint.com/page/Strace+Analyzer

The version that is on the website is currently a bit dated with
a few bugs in it. I should be posting the latest version in the
next couple of weeks.

Thanks!

Jeff