Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932818AbZDJJSQ (ORCPT ); Fri, 10 Apr 2009 05:18:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1763731AbZDJJR5 (ORCPT ); Fri, 10 Apr 2009 05:17:57 -0400 Received: from atrey.karlin.mff.cuni.cz ([195.113.26.193]:38200 "EHLO atrey.karlin.mff.cuni.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761345AbZDJJRy (ORCPT ); Fri, 10 Apr 2009 05:17:54 -0400 Date: Fri, 10 Apr 2009 11:20:48 +0200 From: Pavel Machek To: mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, matthltc@us.ibm.com, nigel@tuxonice.net, akpm@linux-foundation.org, stable@kernel.org, tglx@linutronix.de, ntl@pobox.com, mingo@elte.hu Cc: linux-tip-commits@vger.kernel.org Subject: Re: [tip:sched/urgent] sched: do not count frozen tasks toward load Message-ID: <20090410092048.GA30093@elf.ucw.cz> References: <20090408194512.47a99b95@manatee.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2112 Lines: 47 On Thu 2009-04-09 05:39:32, Nathan Lynch wrote: > Commit-ID: e3c8ca8336707062f3f7cb1cd7e6b3c753baccdd > Gitweb: http://git.kernel.org/tip/e3c8ca8336707062f3f7cb1cd7e6b3c753baccdd > Author: Nathan Lynch > AuthorDate: Wed, 8 Apr 2009 19:45:12 -0500 > Committer: Ingo Molnar > CommitDate: Thu, 9 Apr 2009 07:37:02 +0200 > > sched: do not count frozen tasks toward load > > Freezing tasks via the cgroup freezer causes the load average to climb > because the freezer's current implementation puts frozen tasks in > uninterruptible sleep (D state). > > Some applications which perform job-scheduling functions consult the > load average when making decisions. If a cgroup is frozen, the load > average does not provide a useful measure of the system's utilization > to such applications. This is especially inconvenient if the job > scheduler employs the cgroup freezer as a mechanism for preempting low > priority jobs. Contrast this with using SIGSTOP for the same purpose: > the stopped tasks do not count toward system load. > > Change task_contributes_to_load() to return false if the task is > frozen. This results in /proc/loadavg behavior that better meets > users' expectations. > > Signed-off-by: Nathan Lynch > Acked-by: Andrew Morton > Acked-by: Nigel Cunningham > Tested-by: Nigel Cunningham > Cc: > Cc: containers@lists.linux-foundation.org > Cc: linux-pm@lists.linux-foundation.org > Cc: Matt Helsley > LKML-Reference: <20090408194512.47a99b95@manatee.lan> > Signed-off-by: Ingo Molnar Acked-by: Pavel Machek -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/