From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Ingo Molnar <mingo@elte.hu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
LKML <linux-kernel@vger.kernel.org>,
Andrew Morton <akpm@linux-foundation.org>,
Steven Rostedt <rostedt@goodmis.org>,
Thomas Gleixner <tglx@linutronix.de>,
Tony Lindgren <tony@atomide.com>, Mike Galbraith <efault@gmx.de>
Subject: Re: [RFC PATCH] check_preempt_tick should not compare vruntime with wall time
Date: Mon, 13 Sep 2010 14:19:25 -0400 [thread overview]
Message-ID: <20100913181925.GA15107@Krystal> (raw)
In-Reply-To: <20100913180348.GA20171@elte.hu>
* Ingo Molnar (mingo@elte.hu) wrote:
>
> * Mathieu Desnoyers <mathieu.desnoyers@efficios.com> wrote:
>
> > * Linus Torvalds (torvalds@linux-foundation.org) wrote:
> > > On Mon, Sep 13, 2010 at 9:16 AM, Mathieu Desnoyers
> > > <mathieu.desnoyers@efficios.com> wrote:
> > > >
> > > > OK, the long IRC discussions we just had convinced me that the current scheme
> > > > takes things into account by adapting the granularity dynamically, but also got
> > > > me to notice that check_preempt seems to compare vruntime with wall time, which
> > > > is utterly incorrect. So maybe all my patch was doing was to expose this bug:
> > >
> > > Do you have latency numbers for this patch?
> >
> > Sure, see below,
> >
> > In addition to this patch, [...]
>
> Note, which is a NOP for your latency workload.
>
> > [...] I also used Peter's approach of reducing the minimum granularity
>
> Ok, that's the very first patch i sent yesterday morning - so we also
> have my numbers that it reduces latencies.
>
> To move things along i'll apply it with your Reported-by and Acked-by
> line, ok?
>
> We can also work on the other, more complex things after that, but first
> lets make some progress on the latency front ...
Yep, that's fine with me.
Thanks!
Mathieu
>
> Thanks,
>
> Ingo
--
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com
next prev parent reply other threads:[~2010-09-13 18:19 UTC|newest]
Thread overview: 76+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-11 17:37 [RFC patch 0/2] sched: dynamically adapt granularity with nr_running Mathieu Desnoyers
2010-09-11 17:37 ` [RFC patch 1/2] " Mathieu Desnoyers
2010-09-11 18:57 ` Peter Zijlstra
2010-09-11 19:21 ` Linus Torvalds
2010-09-11 20:36 ` Peter Zijlstra
2010-09-11 20:45 ` Peter Zijlstra
2010-09-11 20:52 ` Linus Torvalds
2010-09-12 9:07 ` Peter Zijlstra
2010-09-11 20:48 ` Linus Torvalds
2010-09-12 9:06 ` Peter Zijlstra
2010-09-12 9:14 ` Peter Zijlstra
2010-09-12 20:39 ` Mathieu Desnoyers
2010-09-13 12:54 ` Peter Zijlstra
2010-09-12 20:34 ` Mathieu Desnoyers
2010-09-13 12:53 ` Peter Zijlstra
2010-09-13 4:35 ` Mike Galbraith
2010-09-13 8:41 ` Peter Zijlstra
2010-09-13 11:22 ` Ingo Molnar
2010-09-13 13:52 ` Steven Rostedt
2010-09-13 13:54 ` Peter Zijlstra
2010-09-13 14:02 ` Peter Zijlstra
2010-09-13 14:21 ` Ingo Molnar
2010-09-11 20:52 ` Mathieu Desnoyers
2010-09-11 19:57 ` Mathieu Desnoyers
2010-09-12 10:41 ` Peter Zijlstra
2010-09-12 20:37 ` Mathieu Desnoyers
2010-09-13 12:53 ` Peter Zijlstra
2010-09-13 13:15 ` Peter Zijlstra
2010-09-13 13:56 ` Mathieu Desnoyers
2010-09-13 14:16 ` Peter Zijlstra
2010-09-13 14:43 ` Steven Rostedt
2010-09-13 15:25 ` Mathieu Desnoyers
2010-09-13 15:39 ` Steven Rostedt
2010-09-13 16:16 ` [RFC PATCH] check_preempt_tick should not compare vruntime with wall time Mathieu Desnoyers
2010-09-13 16:36 ` Linus Torvalds
2010-09-13 17:45 ` Mathieu Desnoyers
2010-09-13 17:51 ` Linus Torvalds
2010-09-13 18:01 ` Mathieu Desnoyers
2010-09-13 18:10 ` Steven Rostedt
2010-09-13 18:03 ` Ingo Molnar
2010-09-13 18:19 ` Mathieu Desnoyers [this message]
2010-09-13 18:23 ` [PATCH] sched: Improve latencies under load by decreasing minimum scheduling granularity Ingo Molnar
2010-09-13 18:28 ` Joe Perches
2010-09-13 19:44 ` Linus Torvalds
2010-09-13 20:00 ` Ingo Molnar
2010-09-13 18:19 ` [RFC PATCH] check_preempt_tick should not compare vruntime with wall time Ingo Molnar
2010-09-13 17:36 ` Ingo Molnar
2010-09-13 17:56 ` Mathieu Desnoyers
2010-09-14 2:10 ` Mike Galbraith
2010-09-13 14:44 ` [RFC patch 1/2] sched: dynamically adapt granularity with nr_running Mike Galbraith
[not found] ` <1284386179.10436.6.camel@marge.simson.net>
2010-09-13 15:53 ` Peter Zijlstra
2010-09-13 18:04 ` [RFC][PATCH] sched: Improve tick preemption Peter Zijlstra
2010-09-14 2:27 ` [RFC patch 1/2] sched: dynamically adapt granularity with nr_running Mike Galbraith
2010-09-12 6:14 ` Ingo Molnar
2010-09-12 7:21 ` Mike Galbraith
2010-09-12 18:16 ` Mathieu Desnoyers
2010-09-13 4:13 ` Mike Galbraith
2010-09-13 6:41 ` Ingo Molnar
2010-09-13 7:08 ` Mike Galbraith
2010-09-13 7:35 ` Mike Galbraith
2010-09-13 8:35 ` Peter Zijlstra
2010-09-13 9:16 ` Mike Galbraith
2010-09-13 9:37 ` Peter Zijlstra
2010-09-13 9:50 ` Mike Galbraith
2010-09-13 9:55 ` Peter Zijlstra
2010-09-13 10:06 ` Mike Galbraith
2010-09-13 10:45 ` Peter Zijlstra
2010-09-13 11:43 ` Peter Zijlstra
2010-09-13 11:49 ` Peter Zijlstra
2010-09-13 12:32 ` Mike Galbraith
2010-09-13 20:19 ` Mathieu Desnoyers
2010-09-13 20:56 ` Mathieu Desnoyers
2010-09-12 18:13 ` Mathieu Desnoyers
2010-09-12 23:44 ` Mathieu Desnoyers
2010-09-11 17:37 ` [RFC patch 2/2] sched: sleepers coarse granularity on wakeup Mathieu Desnoyers
2010-09-12 12:44 ` [RFC patch 0/2] sched: dynamically adapt granularity with nr_running Peter Zijlstra
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=20100913181925.GA15107@Krystal \
--to=mathieu.desnoyers@efficios.com \
--cc=akpm@linux-foundation.org \
--cc=efault@gmx.de \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=peterz@infradead.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
--cc=tony@atomide.com \
--cc=torvalds@linux-foundation.org \
/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