public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Lee Revell <rlrevell@joe-job.com>
To: "Jack O'Quin" <joq@io.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
	Ingo Molnar <mingo@elte.hu>,
	Paul Davis <paul@linuxaudiosystems.com>,
	Con Kolivas <kernel@kolivas.org>,
	linux <linux-kernel@vger.kernel.org>,
	CK Kernel <ck@vds.kolivas.org>, utz <utz@s2y4n2c.de>,
	Andrew Morton <akpm@osdl.org>,
	alexn@dsv.su.se, Rui Nuno Capela <rncbc@rncbc.org>,
	Chris Wright <chrisw@osdl.org>,
	Arjan van de Ven <arjanv@redhat.com>
Subject: Re: [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature
Date: Thu, 27 Jan 2005 15:01:24 -0500	[thread overview]
Message-ID: <1106856085.25754.10.camel@krustophenia.net> (raw)
In-Reply-To: <87pszr1mi1.fsf@sulphur.joq.us>

On Wed, 2005-01-26 at 23:15 -0600, Jack O'Quin wrote:
> >> > And finally, with rlimit support, is there any reason why lockup
> >> > detection and correction can't go into userspace? Even RT
> >> > throttling could probably be done in a userspace daemon.
> >> 
> >> It can.  But, doing it in the kernel is more efficient, and probably
> >> more reliable.
> >
> > Possibly. But the people who want a solution seem to be in a very
> > small minority, and I'm not sure how much you care about efficiency.
> 
> I do care.  The average overhead of running a watchdog daemon at max
> priority is tiny.  But, its impact on worst-case trigger latencies is
> non-trivial and must be added to everything else in the RT subsystem.

Keep in mind that with the max RT prio rlimit solution audio systems
using JACK would not even need the external watchdog thread, because
JACK already has its own watchdog thread.  I also like the max RT prio
rlimit approach with (optional) watchdog thread running as root because
it really seems to be the least intrusive out of several good solutions
to the problem and puts policy details (when to throttle an RT thread)
in userspace.

Lee


  parent reply	other threads:[~2005-01-27 20:03 UTC|newest]

Thread overview: 198+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-01-19 22:39 [PATCH]sched: Isochronous class v2 for unprivileged soft rt scheduling Con Kolivas
2005-01-20  0:16 ` utz lehmann
2005-01-20  0:33   ` Con Kolivas
2005-01-20  4:26     ` utz lehmann
2005-01-20  5:55       ` Con Kolivas
2005-01-20 17:54   ` Alexander Nyberg
2005-01-20 20:27     ` Con Kolivas
2005-01-20  0:53 ` Con Kolivas
2005-01-20  1:32   ` Jack O'Quin
2005-01-20  2:06     ` Con Kolivas
2005-01-20  2:45       ` Jack O'Quin
2005-01-20  4:07         ` Con Kolivas
2005-01-20  4:57           ` Jack O'Quin
2005-01-20  5:05             ` Gene Heskett
2005-01-20  5:59             ` Con Kolivas
2005-01-20  6:35               ` Con Kolivas
2005-01-20 15:19                 ` Jack O'Quin
2005-01-20 15:42                   ` Paul Davis
2005-01-20 16:47                     ` Jack O'Quin
2005-01-20 17:25                       ` Ingo Molnar
2005-01-22  0:09                         ` Jack O'Quin
2005-01-22 16:54                           ` Ingo Molnar
2005-01-22 21:23                             ` Jack O'Quin
2005-01-23  2:06                               ` Nick Piggin
2005-01-23  2:58                                 ` Chris Wright
2005-01-24  8:59                               ` Ingo Molnar
2005-01-24  9:55                                 ` Paolo Ciarrocchi
2005-01-24 10:29                                   ` Nick Piggin
2005-01-24 10:46                                   ` Ingo Molnar
2005-01-24 12:58                                 ` [patch, 2.6.11-rc2] sched: /proc/sys/kernel/rt_cpu_limit tunable Ingo Molnar
2005-01-24 13:34                                   ` Ingo Molnar
2005-01-24 13:53                                   ` Con Kolivas
2005-01-24 14:01                                     ` [ck] " Con Kolivas
     [not found]                                   ` <87k6q2umla.fsf@sulphur.joq.us>
2005-01-25  6:28                                     ` Nick Piggin
2005-01-25 14:12                                       ` Ingo Molnar
2005-01-25  8:37                                     ` Ingo Molnar
2005-01-25 21:36                                       ` Jack O'Quin
2005-01-25 21:49                                         ` Ingo Molnar
2005-01-25 21:55                                           ` Chris Wright
2005-01-25 21:57                                             ` Ingo Molnar
2005-01-25 22:03                                               ` Chris Wright
2005-01-25 22:08                                                 ` Ingo Molnar
2005-01-25 22:16                                                   ` Chris Wright
2005-01-25 22:44                                                 ` Bill Rugolsky Jr.
2005-01-26  5:12                                           ` Jack O'Quin
2005-01-26  7:27                                             ` Ingo Molnar
2005-01-26 11:02                                               ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Ingo Molnar
2005-01-25 13:56                                   ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Ingo Molnar
2005-01-25 14:06                                     ` Con Kolivas
2005-01-25 22:18                                     ` Peter Williams
2005-01-25 22:26                                       ` Peter Williams
2005-01-26 10:08                                         ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Ingo Molnar
2005-01-26 14:22                                           ` Jack O'Quin
2005-01-26 16:18                                           ` [ck] " Cal
2005-01-26 16:29                                             ` Cal
2005-01-26 16:41                                             ` Jack O'Quin
2005-01-26 17:57                                               ` Cal
2005-01-26 18:57                                                 ` Jack O'Quin
2005-01-27  2:03                                                   ` Cal
2005-01-27  8:51                                                     ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D8 Ingo Molnar
2005-01-27 12:48                                                       ` Cal
2005-01-27 16:31                                                       ` Mike Galbraith
2005-01-26 21:28                                           ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU feature, -D7 Peter Williams
2005-01-26 21:44                                           ` Peter Williams
2005-01-26  9:20                                       ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Ingo Molnar
2005-01-31 23:03                                         ` Peter Williams
2005-02-01 10:11                                           ` [patch] sys_setpriority() euid semantics fix Ingo Molnar
2005-02-01 21:46                                             ` Peter Williams
2005-01-26  5:24                                     ` [patch, 2.6.11-rc2] sched: RLIMIT_RT_CPU_RATIO feature Jack O'Quin
2005-01-26  7:04                                       ` Ingo Molnar
2005-01-26 22:27                                         ` Jack O'Quin
2005-01-26 23:29                                           ` Nick Piggin
2005-01-27  2:31                                             ` Jack O'Quin
2005-01-27  3:26                                               ` Nick Piggin
2005-01-27  5:15                                                 ` Jack O'Quin
2005-01-27  5:54                                                   ` Nick Piggin
2005-01-27  8:35                                                     ` Ingo Molnar
2005-01-27  8:59                                                       ` Ingo Molnar
2005-01-27 11:35                                                   ` Ingo Molnar
2005-02-02  5:10                                                     ` Jack O'Quin
2005-02-02 11:10                                                       ` Bill Huey
2005-02-02 16:44                                                         ` Jack O'Quin
2005-02-02 21:14                                                           ` Bill Huey
2005-02-02 21:20                                                             ` Bill Huey
2005-02-02 21:21                                                             ` Ingo Molnar
2005-02-02 21:34                                                               ` Bill Huey
2005-02-02 22:59                                                                 ` Paul Davis
2005-02-03  2:46                                                                   ` Bill Huey
2005-02-03 14:20                                                                     ` Paul Davis
2005-02-03 20:19                                                                       ` Con Kolivas
2005-02-03 20:47                                                                         ` Ingo Molnar
2005-02-03 21:15                                                                           ` Paul Davis
2005-02-03 21:28                                                                             ` Ingo Molnar
2005-02-03 21:41                                                                               ` Paul Davis
2005-02-03 21:59                                                                                 ` Ingo Molnar
2005-02-03 22:24                                                                                   ` Paul Davis
2005-02-03 22:26                                                                                     ` Ingo Molnar
2005-02-04  0:36                                                                           ` Tristan Wibberley
2005-02-03 21:48                                                                       ` Peter Williams
2005-02-04 16:41                                                                         ` Jack O'Quin
2005-02-04 21:38                                                                           ` Peter Williams
2005-02-03 21:41                                                                 ` Ingo Molnar
2005-02-03 23:01                                                                   ` Bill Huey
2005-02-11 21:27                                                                   ` Lee Revell
2005-02-02 21:54                                                         ` Peter Williams
2005-02-02 23:03                                                           ` Paul Davis
2005-02-02 23:46                                                             ` Peter Williams
2005-02-03  1:13                                                               ` Jack O'Quin
2005-02-03  3:10                                                                 ` Peter Williams
2005-02-03  3:56                                                                   ` Jack O'Quin
2005-02-03 21:36                                                             ` Ingo Molnar
2005-02-04  0:35                                                               ` Chris Wright
2005-02-04 17:21                                                               ` Jack O'Quin
2005-02-03  2:54                                                           ` Bill Huey
2005-02-03  3:25                                                             ` Peter Williams
2005-02-02 11:37                                                       ` Ingo Molnar
2005-02-02 16:01                                                         ` Jack O'Quin
2005-02-02 18:59                                                       ` Lee Revell
2005-02-02 19:31                                                         ` Jack O'Quin
2005-02-02 20:29                                                           ` Ingo Molnar
2005-02-02 22:45                                                             ` Jack O'Quin
2005-02-02 20:17                                                       ` Ingo Molnar
2005-01-27 20:01                                                   ` Lee Revell [this message]
2005-01-28  6:38                                                 ` Ingo Molnar
2005-01-28  8:09                                                   ` Jack O'Quin
2005-01-28  8:08                                             ` Ingo Molnar
2005-01-28  8:35                                               ` Jack O'Quin
2005-01-28  8:40                                                 ` Ingo Molnar
2005-01-28  9:01                                                   ` Jack O'Quin
2005-01-28  9:11                                                     ` Ingo Molnar
2005-01-29  0:44                                                       ` Lee Revell
2005-01-28  9:51                                                     ` Mike Galbraith
2005-01-28 22:16                                                   ` Peter Williams
2005-01-28 22:19                                                     ` Ingo Molnar
2005-01-29  7:02                                                     ` Jack O'Quin
2005-01-31 22:29                                                   ` Bill Davidsen
2005-02-01  0:39                                                     ` Bill Huey
2005-01-25  5:16                                 ` [PATCH]sched: Isochronous class v2 for unprivileged soft rt scheduling Jack O'Quin
2005-01-25 15:09                                   ` Ingo Molnar
2005-01-23 20:48                             ` Jack O'Quin
2005-01-23 22:57                               ` Con Kolivas
2005-01-24  1:06                                 ` Jack O'Quin
2005-01-24  1:09                                   ` Con Kolivas
2005-01-24  4:45                                     ` Jack O'Quin
2005-01-24  4:53                                       ` Jack O'Quin
2005-01-24  6:28                                         ` Jack O'Quin
2005-01-24  6:35                                           ` Con Kolivas
2005-01-24  6:57                                             ` Jack O'Quin
2005-01-24 22:58                                               ` Con Kolivas
2005-01-25  3:55                                                 ` Con Kolivas
2005-01-25 13:05                                                   ` Con Kolivas
2005-01-25 14:38                                                     ` Con Kolivas
2005-01-25 18:36                                                     ` Jack O'Quin
2005-01-25 20:52                                                       ` Rui Nuno Capela
2005-01-24 21:46                                           ` Con Kolivas
2005-01-23  7:38                           ` Jack O'Quin
2005-01-23  7:41                             ` Con Kolivas
2005-01-24  6:30                         ` Jack O'Quin
2005-01-24 20:55                           ` Ingo Molnar
2005-01-20 21:59                       ` Peter Chubb
2005-01-21  0:30                         ` Jack O'Quin
2005-01-22 14:06                         ` Paul Davis
2005-01-20 17:49                     ` ross
2005-01-20 19:07                       ` Lee Revell
2005-01-20 23:17                       ` Con Kolivas
2005-01-21  7:48                         ` Ingo Molnar
2005-02-07  3:09               ` Werner Almesberger
2005-02-07  3:27                 ` Jack O'Quin
2005-02-07  3:27                   ` Con Kolivas
2005-01-20  9:06             ` Rui Nuno Capela
2005-01-20 17:09               ` Rui Nuno Capela
2005-01-20 19:32                 ` Jack O'Quin
2005-01-21  9:18                   ` Rui Nuno Capela
2005-01-21 16:23                     ` Con Kolivas
2005-01-21 16:40                       ` Jack O'Quin
2005-01-22  0:06                 ` Con Kolivas
2005-01-22  6:18                   ` Jack O'Quin
2005-01-22  6:19                     ` Con Kolivas
2005-01-22  6:48                     ` Con Kolivas
2005-01-22  6:50                       ` Con Kolivas
2005-01-22  7:09                         ` Con Kolivas
2005-01-22 20:22                           ` Jack O'Quin
2005-01-23  1:02                             ` Con Kolivas
2005-01-23  3:02                               ` Jack O'Quin
2005-01-23  4:29                                 ` Con Kolivas
2005-01-23  4:46                                   ` Jack O'Quin
2005-01-23  4:50                                     ` Con Kolivas
2005-01-23  7:37                                       ` Mike Galbraith
2005-01-23 13:57                                         ` Paul Davis
2005-01-23  1:31                             ` Con Kolivas
2005-01-23  1:41                               ` Paul Davis
2005-01-23  1:56                                 ` Con Kolivas
2005-01-23  4:50                                   ` Jack O'Quin
2005-01-21 23:30 ` utz lehmann
2005-01-21 23:48   ` Con Kolivas
2005-01-22  0:28     ` utz lehmann
2005-01-22  3:52       ` Con Kolivas
2005-01-22  6:15         ` Jack O'Quin

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=1106856085.25754.10.camel@krustophenia.net \
    --to=rlrevell@joe-job.com \
    --cc=akpm@osdl.org \
    --cc=alexn@dsv.su.se \
    --cc=arjanv@redhat.com \
    --cc=chrisw@osdl.org \
    --cc=ck@vds.kolivas.org \
    --cc=joq@io.com \
    --cc=kernel@kolivas.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=nickpiggin@yahoo.com.au \
    --cc=paul@linuxaudiosystems.com \
    --cc=rncbc@rncbc.org \
    --cc=utz@s2y4n2c.de \
    /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