From: Dave Chinner <david@fromorbit.com>
To: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Cc: Matthew Whittaker-Williams <matthew@xsnews.nl>, xfs@oss.sgi.com
Subject: Re: XFS hangs and freezes with LSI 9265-8i controller on high i/o
Date: Fri, 15 Jun 2012 22:30:34 +1000 [thread overview]
Message-ID: <20120615123034.GC19223@dastard> (raw)
In-Reply-To: <4FDB1BA6.3030203@itwm.fraunhofer.de>
On Fri, Jun 15, 2012 at 01:25:26PM +0200, Bernd Schubert wrote:
> On 06/15/2012 02:16 AM, Dave Chinner wrote:
> >Oh, I just noticed you are might be using CFQ (it's the default in
> >dmesg). Don't - CFQ is highly unsuited for hardware RAID - it's
> >hueristically tuned to work well on sngle SATA drives. Use deadline,
> >or preferably for hardware RAID, noop.
>
> I'm not sure if noop is really a good recommendation even with hw
> raid, especially if the the request queue size is high. This week I
> did some benchmarks with a high rq write size (triggered with
> sync_file_range(..., SYNC_FILE_RANGE_WRITE) ) and with noop
> concuring reads then almost entirely got stalled.
> With deadline read/write balance was much better, although writes
> still had been preferred (with sync_file_range() and without). I
> always thought deadline prefers reads and I hope I find some time
> later on to investigate further what was going on.
> Test had been on a netapp E5400 hw raid, so rather high end hw raid.
Sounds like a case of the IO scheduler queue and/or CTQ being too
deep.
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next prev parent reply other threads:[~2012-06-15 12:30 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-11 21:37 XFS hangs and freezes with LSI 9265-8i controller on high i/o Matthew Whittaker-Williams
2012-06-12 1:18 ` Dave Chinner
2012-06-12 15:56 ` Matthew Whittaker-Williams
2012-06-12 17:40 ` Matthew Whittaker-Williams
2012-06-13 0:12 ` Stan Hoeppner
2012-06-13 1:19 ` Dave Chinner
2012-06-13 3:56 ` Stan Hoeppner
2012-06-13 8:54 ` Matthew Whittaker-Williams
2012-06-13 11:59 ` Andre Noll
2012-06-13 12:13 ` Michael Monnerie
2012-06-13 16:12 ` Stan Hoeppner
2012-06-14 7:31 ` Michael Monnerie
2012-06-14 0:04 ` Dave Chinner
2012-06-14 14:31 ` Matthew Whittaker-Williams
2012-06-15 0:16 ` Dave Chinner
2012-06-15 9:52 ` Michael Monnerie
2012-06-15 12:29 ` Dave Chinner
2012-06-15 11:25 ` Bernd Schubert
2012-06-15 12:30 ` Dave Chinner [this message]
2012-06-15 14:22 ` Bernd Schubert
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20120615123034.GC19223@dastard \
--to=david@fromorbit.com \
--cc=bernd.schubert@itwm.fraunhofer.de \
--cc=matthew@xsnews.nl \
--cc=xfs@oss.sgi.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.