From: Jens Axboe <jens.axboe@oracle.com>
To: Corrado Zoccolo <czoccolo@gmail.com>
Cc: Linux-Kernel <linux-kernel@vger.kernel.org>, knikanth@suse.de
Subject: Re: [bisected] commit: a9327cac440be4d8333bba975cbbf76045096275 causes iostat output
Date: Sun, 4 Oct 2009 21:06:53 +0200 [thread overview]
Message-ID: <20091004190653.GH26573@kernel.dk> (raw)
In-Reply-To: <4e5e476b0910040349l21b69a97o7a11b2138bc8f573@mail.gmail.com>
On Sun, Oct 04 2009, Corrado Zoccolo wrote:
> Hi,
> with 2.6.32-rc1 I started getting the following strange output from
> "iostat -kx 2":
> Linux 2.6.31bisect (et2) 04/10/2009 _i686_ (2 CPU)
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 10,70 0,00 3,16 15,75 0,00 70,38
>
> Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s
> avgrq-sz avgqu-sz await svctm %util
> sda 18,22 0,00 0,67 0,01 14,77 0,02
> 43,94 0,01 10,53 39043915,03 2629219,87
> sdb 60,89 9,68 50,79 3,04 1724,43 50,52
> 65,95 0,70 13,06 488437,47 2629219,87
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 2,72 0,00 0,74 0,00 0,00 96,53
>
> Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s
> avgrq-sz avgqu-sz await svctm %util
> sda 0,00 0,00 0,00 0,00 0,00 0,00
> 0,00 0,00 0,00 0,00 100,00
> sdb 0,00 0,00 0,00 0,00 0,00 0,00
> 0,00 0,00 0,00 0,00 100,00
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 6,68 0,00 0,99 0,00 0,00 92,33
>
> Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s
> avgrq-sz avgqu-sz await svctm %util
> sda 0,00 0,00 0,00 0,00 0,00 0,00
> 0,00 0,00 0,00 0,00 100,00
> sdb 0,00 0,00 0,00 0,00 0,00 0,00
> 0,00 0,00 0,00 0,00 100,00
>
> avg-cpu: %user %nice %system %iowait %steal %idle
> 4,40 0,00 0,73 1,47 0,00 93,40
>
> Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s
> avgrq-sz avgqu-sz await svctm %util
> sda 0,00 0,00 0,00 0,00 0,00 0,00
> 0,00 0,00 0,00 0,00 100,00
> sdb 0,00 4,00 0,00 3,00 0,00 28,00
> 18,67 0,06 19,50 333,33 100,00
>
> Global values for service time and utilization are garbage. For
> interval values, utilization is always 100%, and service time is
> higher than normal.
>
> I bisected it down to:
> [a9327cac440be4d8333bba975cbbf76045096275] Seperate read and write
> statistics of in_flight requests
> and verified that reverting just that commit indeed solves the issue
> on 2.6.32-rc1.
I've reverted this commit since the next -rc is close, then we can debug
and potentially re-introduce this change after that. Thanks a lot for
reporting and bisecting it, too!
--
Jens Axboe
next prev parent reply other threads:[~2009-10-04 19:07 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-04 10:49 [bisected] commit: a9327cac440be4d8333bba975cbbf76045096275 causes iostat output Corrado Zoccolo
2009-10-04 19:06 ` Jens Axboe [this message]
2009-10-06 13:14 ` Nikanth Karthikesan
2009-10-06 13:16 ` [PATCH linux-2.6-block#for-linus] Seperate read and write statistics of in_flight requests v2 Nikanth Karthikesan
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=20091004190653.GH26573@kernel.dk \
--to=jens.axboe@oracle.com \
--cc=czoccolo@gmail.com \
--cc=knikanth@suse.de \
--cc=linux-kernel@vger.kernel.org \
/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.