linux-kernel - Re: Why is kslowd accumulating so much CPU time?

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 15 Jun 2010 18:25:42 +0100
From:	Andy Whitcroft <apw@...onical.com>
To:	tytso@....edu, Dave Airlie <airlied@...il.com>,
	Dave Airlie <airlied@...hat.com>,
	David Howells <dhowells@...hat.com>,
	linux-kernel@...r.kernel.org
Subject: Re: Why is kslowd accumulating so much CPU time?

On Mon, Jun 14, 2010 at 10:46 PM,  <tytso@....edu> wrote:
> On Mon, Jun 14, 2010 at 02:42:44PM -0400, Nick Bowler wrote:
>>
>> This sounds exactly like the issue I've been seeing on a T500 laptop, as
>> well (GM45 board).  The slowdowns render the system essentially
>> unusable, as it can spend a loooong time just moving the mouse cursor a
>> few pixels on the screen.  During this time, nothing else on the display
>> is updating (glxgears drops to 0fps).  Things generally seem to be
>> working fine if I am not moving the mouse, or if I'm not running X.
>
> I saw exactly the same behaviour when using the Ubuntu Karmic
> userspace.  Basically, using a 2.6.35-rc2 (+ vt memory corrupter fix)
> kernel, the system was essentially unusable.  Interestingly, the
> problem went away (with the same kernel) once I updated to Ubuntu
> Lucid.  I was going to mention that so that hopefully someone with far
> more X.org-fu than I could figure out how much of this is a X server
> bug, and how much of this was a kernel bug, but things worked just
> *fine* with 2.6.34 kernel.
>
> Occasionally it will happen that the mouse stops tracking, and then I
> grumble and curse, and a few seconds later it resolves itself.  I
> haven't had time to track it down; but the problem was breathtakingly
> easy to reproduce with an Ubuntu Karmic userspace.  :-)

I am seeing crunchy cursor behavior on boot on Ubuntu Lucid user space
with the 2.6.35-rc3 kernel as well.  It pretty much always does that
on boot, and often later as well.  Right now I have four of these
chaps each consuming 9% of a CPU.  Though they definatly come and go.
Very odd:

  938 root      15  -5     0    0    0 S    9  0.0   1:00.90 kslowd001
 1048 root      15  -5     0    0    0 S    9  0.0   1:01.12 kslowd002
  937 root      15  -5     0    0    0 S    8  0.0   1:00.92 kslowd000
 1544 root      15  -5     0    0    0 D    8  0.0   1:00.55 kslowd003

-apw
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/