public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Peter Zijlstra <peterz@infradead.org>
To: Harald Gustafsson <hgu1972@gmail.com>
Cc: Harald Gustafsson <harald.gustafsson@ericsson.com>,
	Dario Faggioli <faggioli@gandalf.sssup.it>,
	linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
	Thomas Gleixner <tglx@linutronix.de>,
	Claudio Scordino <claudio@evidence.eu.com>,
	Michael Trimarchi <trimarchi@retis.sssup.it>,
	Fabio Checconi <fabio@gandalf.sssup.it>,
	Tommaso Cucinotta <cucinotta@sssup.it>,
	Juri Lelli <juri.lelli@gmail.com>,
	Dario Faggioli <raistlin@linux.it>
Subject: Re: [PATCH 1/3] Added runqueue clock normalized with cpufreq
Date: Fri, 17 Dec 2010 16:16:47 +0100	[thread overview]
Message-ID: <1292599007.2266.290.camel@twins> (raw)
In-Reply-To: <AANLkTinGkf3a4_sw32b4UqAmpUU+i6fDmDUT8tXdw14D@mail.gmail.com>

On Fri, 2010-12-17 at 16:06 +0100, Harald Gustafsson wrote:
> 2010/12/17 Peter Zijlstra <peterz@infradead.org>:
> > This is all assuming lowering the frequency is sensible to begin with in
> > the first place... but that's all part of the CPUfreq governor, it needs
> > to find a way to lower energy usage while conforming to the system
> > constraints.
> 
> Yes, I and you have already suggested the safe way to not lower it below
> the total dl bandwidth. But for softer use cases it might be possible to
> e.g. exclude threads with longer periods than cpufreq change periods in the
> minimum frequency.

I was more hinting at the fact that CPUfreq is at best a controversial
approach to power savings. I much prefer the whole race-to-idle
approach, its much simpler.

  reply	other threads:[~2010-12-17 15:17 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-12-17 13:02 [PATCH 1/3] Added runqueue clock normalized with cpufreq Harald Gustafsson
2010-12-17 13:02 ` [PATCH 2/3] cpufreq normalized runtime to enforce runtime cycles also at lower frequencies Harald Gustafsson
2010-12-17 13:02 ` [PATCH 3/3] sched trace updated with normalized clock info Harald Gustafsson
2010-12-17 14:29 ` [PATCH 1/3] Added runqueue clock normalized with cpufreq Peter Zijlstra
2010-12-17 14:32   ` Peter Zijlstra
2010-12-17 15:06     ` Harald Gustafsson
2010-12-17 15:16       ` Peter Zijlstra [this message]
2010-12-17 15:36         ` Harald Gustafsson
2010-12-17 15:43         ` Thomas Gleixner
2010-12-17 15:54           ` Harald Gustafsson
2010-12-17 18:44           ` Dario Faggioli
2011-01-03 14:17           ` Pavel Machek
2010-12-17 15:02   ` Harald Gustafsson
2010-12-17 18:48     ` Dario Faggioli
2010-12-17 18:56   ` Dario Faggioli
2010-12-17 18:59     ` Peter Zijlstra
2010-12-17 19:16       ` Dario Faggioli
2010-12-17 19:31       ` Harald Gustafsson
2010-12-20  0:11         ` Tommaso Cucinotta
2010-12-20  9:44           ` Harald Gustafsson
2011-01-03 20:25             ` Tommaso Cucinotta
2011-01-04 12:16               ` Harald Gustafsson
2010-12-17 19:27     ` Harald Gustafsson

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=1292599007.2266.290.camel@twins \
    --to=peterz@infradead.org \
    --cc=claudio@evidence.eu.com \
    --cc=cucinotta@sssup.it \
    --cc=fabio@gandalf.sssup.it \
    --cc=faggioli@gandalf.sssup.it \
    --cc=harald.gustafsson@ericsson.com \
    --cc=hgu1972@gmail.com \
    --cc=juri.lelli@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=raistlin@linux.it \
    --cc=tglx@linutronix.de \
    --cc=trimarchi@retis.sssup.it \
    /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