From: Matthew Garrett <mjg59@srcf.ucam.org>
To: Arjan van de Ven <arjan@infradead.org>
Cc: linux-kernel@vger.kernel.org, lenb@kernel.org, mingo@elte.hu,
akpm@linux-foundation.org, peterz@infradead.org,
yanmin_zhang@linux.intel.com, torvalds@linux-foundation.org,
jens.axboe@oracle.com
Subject: Re: PATCH] cpuidle: A new variant of the menu governor to boost IO performance
Date: Sat, 12 Sep 2009 12:39:39 +0100 [thread overview]
Message-ID: <20090912113939.GA7119@srcf.ucam.org> (raw)
In-Reply-To: <20090912052647.3b6dcb78@infradead.org>
On Sat, Sep 12, 2009 at 05:26:47AM +0200, Arjan van de Ven wrote:
> On Fri, 11 Sep 2009 23:03:09 +0100
> Matthew Garrett <mjg59@srcf.ucam.org> wrote:
>
> > When you say that a bit more power was used, is that instantaneous
> > power draw or total power consumption over the run of the benchmark?
> > I'd have expected that completing it 50% faster and then going idle
> > would be a win overall.
>
> I meant power, not total energy :-)
>
> in terms of energy it's a win if you only do a fixed amount of work...
Ok, so not really a downside. Not entirely relatedly, we've also seen io
throughput issues related to P-states - using ondemand, we get reduced
throughput until the number of clients becomes high enough to push the
system into a higher P state. Is this something you've been able to
measure?
--
Matthew Garrett | mjg59@srcf.ucam.org
next prev parent reply other threads:[~2009-09-12 11:39 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-11 15:40 PATCH] cpuidle: A new variant of the menu governor to boost IO performance Arjan van de Ven
2009-09-11 16:37 ` Jens Axboe
2009-09-11 19:16 ` John Stoffel
2009-09-11 19:51 ` Arjan van de Ven
2009-09-14 3:30 ` Zhang, Yanmin
2009-09-11 22:03 ` Matthew Garrett
2009-09-12 3:26 ` Arjan van de Ven
2009-09-12 11:39 ` Matthew Garrett [this message]
2009-09-12 14:04 ` Arjan van de Ven
2009-09-13 23:30 ` Andrew Morton
2009-09-14 2:45 ` Arjan van de Ven
2009-09-14 7:43 ` Andrew Morton
2009-09-14 8:04 ` Tejun Heo
2009-09-14 8:15 ` Peter Zijlstra
2009-09-14 9:09 ` Tejun Heo
2009-09-14 20:31 ` Arjan van de Ven
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=20090912113939.GA7119@srcf.ucam.org \
--to=mjg59@srcf.ucam.org \
--cc=akpm@linux-foundation.org \
--cc=arjan@infradead.org \
--cc=jens.axboe@oracle.com \
--cc=lenb@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=peterz@infradead.org \
--cc=torvalds@linux-foundation.org \
--cc=yanmin_zhang@linux.intel.com \
/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