From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Daniel Walker <dwalker@mvista.com>
Cc: john stultz <johnstul@us.ibm.com>, Andi Kleen <ak@suse.de>,
Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>,
Con Kolivas <kernel@kolivas.org>,
Rusty Russell <rusty@rustcorp.com.au>,
Zachary Amsden <zach@vmware.com>,
James Morris <jmorris@namei.org>,
Chris Wright <chrisw@sous-sol.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
cpufreq@lists.linux.org.uk,
Virtualization Mailing List <virtualization@lists.osdl.org>,
Peter Chubb <peterc@gelato.unsw.edu.au>
Subject: Re: Stolen and degraded time and schedulers
Date: Wed, 14 Mar 2007 14:42:56 -0700 [thread overview]
Message-ID: <45F86C60.7060903@goop.org> (raw)
In-Reply-To: <1173908065.3101.97.camel@imap.mvista.com>
Daniel Walker wrote:
> It's used for measuring execution time, but timers are triggered based
> on that time, so it needs to be actual execution time. I don't know to
> what extent this is already inaccurate on some system tho.
>
Well, "actual execution time" is a bit ambiguous: should that be "time
actually spent executing", or "time we should have spent executing"?
It looks like cpu_clock_sample() will only return accurate results on
yourself; if you get the sched_ns on a thread on another cpu, it won't
include the time accumulated since the start of its timeslice.
J
next prev parent reply other threads:[~2007-03-14 21:43 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-03-13 16:31 Stolen and degraded time and schedulers Jeremy Fitzhardinge
2007-03-13 20:12 ` john stultz
2007-03-13 20:32 ` Jeremy Fitzhardinge
2007-03-13 21:27 ` Daniel Walker
2007-03-13 21:59 ` Jeremy Fitzhardinge
2007-03-14 0:43 ` Dan Hecht
2007-03-14 4:37 ` Jeremy Fitzhardinge
2007-03-14 13:58 ` Lennart Sorensen
2007-03-14 15:08 ` Jeremy Fitzhardinge
2007-03-14 15:12 ` Lennart Sorensen
2007-03-14 19:02 ` Dan Hecht
2007-03-14 19:34 ` Jeremy Fitzhardinge
2007-03-14 19:45 ` Rik van Riel
2007-03-14 19:47 ` Jeremy Fitzhardinge
2007-03-14 20:02 ` Rik van Riel
2007-03-14 20:26 ` Dan Hecht
2007-03-14 20:31 ` Jeremy Fitzhardinge
2007-03-14 20:46 ` Dan Hecht
2007-03-14 21:18 ` Jeremy Fitzhardinge
2007-03-15 19:09 ` Dan Hecht
2007-03-15 19:18 ` Jeremy Fitzhardinge
2007-03-15 19:48 ` Rik van Riel
2007-03-15 19:53 ` Jeremy Fitzhardinge
2007-03-15 20:07 ` Dan Hecht
2007-03-15 20:14 ` Rik van Riel
2007-03-15 20:35 ` Dan Hecht
2007-03-16 8:59 ` Martin Schwidefsky
2007-03-14 20:38 ` Ingo Molnar
2007-03-14 20:59 ` Jeremy Fitzhardinge
2007-03-16 8:38 ` Ingo Molnar
2007-03-16 16:53 ` Jeremy Fitzhardinge
2007-03-15 5:23 ` Paul Mackerras
2007-03-15 19:33 ` Jeremy Fitzhardinge
2007-03-14 2:00 ` Daniel Walker
2007-03-14 6:52 ` Jeremy Fitzhardinge
2007-03-14 8:20 ` Zan Lynx
2007-03-14 16:11 ` Daniel Walker
2007-03-14 16:37 ` Jeremy Fitzhardinge
2007-03-14 16:59 ` Daniel Walker
2007-03-14 17:08 ` Jeremy Fitzhardinge
2007-03-14 18:06 ` Daniel Walker
2007-03-14 18:41 ` Jeremy Fitzhardinge
2007-03-14 19:00 ` Daniel Walker
2007-03-14 19:44 ` Jeremy Fitzhardinge
2007-03-14 20:33 ` Daniel Walker
2007-03-14 21:16 ` Jeremy Fitzhardinge
2007-03-14 21:34 ` Daniel Walker
2007-03-14 21:42 ` Jeremy Fitzhardinge [this message]
2007-03-14 21:36 ` Con Kolivas
2007-03-14 21:38 ` Jeremy Fitzhardinge
2007-03-14 21:40 ` Con Kolivas
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