public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Jens Axboe <jens.axboe@oracle.com>
To: Pawel S <spawels13@gmail.com>
Cc: linux-kernel@vger.kernel.org, Ben Gamari <bgamari.foss@gmail.com>,
	tytso <tytso@mit.edu>, Nick Piggin <npiggin@suse.de>,
	Ingo Molnar <mingo@elte.hu>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: Poor interactive performance with I/O loads with fsync()ing
Date: Tue, 23 Mar 2010 14:27:19 +0100	[thread overview]
Message-ID: <20100323132719.GY5768@kernel.dk> (raw)
In-Reply-To: <8c4cf08c1003230428t274b8ca8y13d67d65b8830dd7@mail.gmail.com>

On Tue, Mar 23 2010, Pawel S wrote:
> Hello
> 
> I am experiencing very similar issue. My system is a regular desktop
> PC and it suffers from very high I/O latencies (sometimes desktop
> "hangs" for eight seconds or more) when copying large files. I tried
> kernels up to 2.6.34-rc2, but without luck. This issue was raised at
> Phoronix forums and Arjan (from Intel) noticed it can be VM related:
> 
> http://www.phoronix.com/forums/showpost.php?p=114975&postcount=51
> 
> Here is my perf timechart where you can notice I/O "steals" CPU from
> the other tasks:
> 
> http://hotfile.com/dl/30596827/ebe566b/output.svg.gz.html

It's also been my sneaking suspicion that swap is involved. I had lots
of RAM in anything I use, even the laptop and workstation. I'll try and
run some tests with lower memory and force it into swap, I've seen nasty
hangs that way.

-- 
Jens Axboe


  reply	other threads:[~2010-03-23 13:27 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-23 11:28 Poor interactive performance with I/O loads with fsync()ing Pawel S
2010-03-23 13:27 ` Jens Axboe [this message]
2010-03-26  3:35   ` Ben Gamari
2010-03-30 10:46   ` Pawel S
  -- strict thread matches above, loose matches on Subject: below --
2010-03-16 15:31 Ben Gamari
2010-03-17  1:24 ` tytso
2010-03-17  3:18   ` Ben Gamari
2010-03-17  3:30     ` tytso
2010-03-17  4:31       ` Ben Gamari
2010-03-26  3:16         ` Ben Gamari
2010-03-17  4:53 ` Nick Piggin
2010-03-17  9:37   ` Ingo Molnar
2010-03-26  3:31     ` Ben Gamari
2010-04-09 15:21     ` Ben Gamari
2010-03-26  3:28   ` Ben Gamari
2010-03-23 19:51 ` Jesper Krogh
2010-03-26  3:13 ` Ben Gamari
2010-03-28  1:20 ` Ben Gamari
2010-03-28  1:29   ` Ben Gamari
2010-03-28  3:42   ` Arjan van de Ven
2010-03-28 14:06     ` Ben Gamari
2010-03-28 22:08       ` Andi Kleen
2010-04-09 14:56         ` Ben Gamari
2010-04-11 15:03           ` Avi Kivity
2010-04-11 16:35             ` Ben Gamari
2010-04-11 17:20               ` Andi Kleen
2010-04-11 18:16             ` Thomas Gleixner
2010-04-11 18:42               ` Andi Kleen
2010-04-11 21:54                 ` Thomas Gleixner
2010-04-11 23:43                   ` Hans-Peter Jansen
2010-04-12  0:22               ` Dave Chinner
2010-04-14 18:40                 ` Ric Wheeler

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=20100323132719.GY5768@kernel.dk \
    --to=jens.axboe@oracle.com \
    --cc=akpm@linux-foundation.org \
    --cc=bgamari.foss@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=npiggin@suse.de \
    --cc=spawels13@gmail.com \
    --cc=tytso@mit.edu \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox