linux-kernel - Re: 'autogroup' sched code KILLING responsiveness

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 for Android: free password hash cracker in your pocket

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

Date:	Sat, 22 Jan 2011 04:22:34 +0100
From:	Mike Galbraith <efault@....de>
To:	Michael Witten <mfwitten@...il.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: 'autogroup' sched code KILLING responsiveness

On Fri, 2011-01-21 at 16:39 -0600, Michael Witten wrote:
> On Fri, Jan 21, 2011 at 16:27, Mike Galbraith <efault@....de> wrote:
> > On Fri, 2011-01-21 at 10:20 -0800, Michael Witten wrote:
> >> Bisecting shows that this commit:
> >>
> >>   5091faa449ee0b7d73bc296a93bca9540fc51d0a
> >>   sched: Add 'autogroup' scheduling feature: automated per session task groups
> >>   Date:   Tue Nov 30 14:18:03 2010 +0100
> >>
> >> is the reason that my computer has become unusable.
> >>
> >> With that code in place, a resource-intensive activity (such as
> >> compiling the Linux kernel) causes my computer to become
> >> unresponsive for many seconds at a time; the entire screen
> >> does not refresh, typed keys are dropped or are handled very
> >> late, etc (even in Linux's plain virtual consoles).
> >
> > That's not what I'm experiencing with a UP kernel...
> 
> Before I try to gather any data, I'd like to point out that the
> problem disappears when I disable CONFIG_SCHED_AUTOGROUP (General
> setup -> Automatic process group scheduling).
> 
> Do you have it disabled?

No, ff I did, mplayer wouldn't be able to get more than 1% cpu.

top - 22:34:38 up 33 min, 22 users,  load average: 104.07, 101.73, 78.13
Tasks: 675 total, 101 running, 574 sleeping,   0 stopped,   0 zombie
Cpu(s): 95.2%us,  4.8%sy,  0.0%ni,  0.0%id,  0.0%wa,  0.0%hi,  0.0%si,  0.0%st

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  P COMMAND                                                              
 6770 root      20   0  401m  79m  29m R 46.9  1.0   3:22.66 0 mplayer                                                              
 6100 root      20   0  449m  94m  18m S  2.9  1.2   1:33.82 0 Xorg                                                                 
 7486 root      20   0  374m  46m  17m S  2.9  0.6   0:54.02 0 konsole

	-Mike


--
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/