From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755425AbXD0GxE (ORCPT ); Fri, 27 Apr 2007 02:53:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755432AbXD0GxE (ORCPT ); Fri, 27 Apr 2007 02:53:04 -0400 Received: from server021.webpack.hosteurope.de ([80.237.130.29]:34355 "EHLO server021.webpack.hosteurope.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755425AbXD0GxB (ORCPT ); Fri, 27 Apr 2007 02:53:01 -0400 From: Michael Gerdau Organization: Technosis GmbH To: Con Kolivas Subject: Re: [ck] Re: [REPORT] cfs-v6-rc2 vs sd-0.46 vs 2.6.21-rc7 Date: Fri, 27 Apr 2007 07:59:07 +0200 User-Agent: KMail/1.9.5 Cc: ck@vds.kolivas.org, Ingo Molnar , Nick Piggin , Bill Davidsen , Juliusz Chroboczek , Mike Galbraith , linux-kernel@vger.kernel.org, William Lee Irwin III , Peter Williams , Gene Heskett , Willy Tarreau , Thomas Gleixner , Linus Torvalds , Andrew Morton , Arjan van de Ven References: <200704261312.25571.mgd@technosis.de> <20070426120723.GA4092@elte.hu> <200704270859.37931.kernel@kolivas.org> In-Reply-To: <200704270859.37931.kernel@kolivas.org> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart1563788.bnKDMgynq7"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <200704270759.23265.mgd@technosis.de> X-bounce-key: webpack.hosteurope.de;mgd@technosis.de;1177656781;8b32656d; Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --nextPart1563788.bnKDMgynq7 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline > Very interesting indeed but fairly complicated as well. Sorry for that -- I've taken these figures from the 3MB logfile that each job creates and "reading" them on a regular basis tend to forget that probably everyody else does not find them as obvious as I do. Also I'm don't really have lots of experience with how a scheduler is properly tested. =46or any upcoming tests I will restrict the numbers to wallclock and what time provides which probably is better suited anyway. > > as a summary: i think your numbers demonstrate it nicely that the > > shorter 'timeslice length' that both CFS and SD utilizes does not have a > > measurable negative impact on your workload. To measure the total impact > > of 'timeslicing' you might want to try the exact same workload with a > > much higher 'timeslice length' of say 400 msecs, via: > > > > echo 400000000 > /proc/sys/kernel/sched_granularity_ns # on CFS > > echo 400 > /proc/sys/kernel/rr_interval # on SD >=20 > I thought that the effective "timeslice" on CFS was double the=20 > sched_granularity_ns so wouldn't this make the effective timeslice double= =20 > that of what you're setting SD to? Anyway the difference between 400 and= =20 > 800ms timeslices is unlikely to be significant so I don't mind. I'm happy to do that, hopefully over the weekend. Best, Michael =2D-=20 Technosis GmbH, Gesch=E4ftsf=FChrer: Michael Gerdau, Tobias Dittmar Sitz Hamburg; HRB 89145 Amtsgericht Hamburg Vote against SPAM - see http://www.politik-digital.de/spam/ Michael Gerdau email: mgd@technosis.de GPG-keys available on request or at public keyserver --nextPart1563788.bnKDMgynq7 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQBGMZE7UYYhyuxDQc4RAsRCAJ9OPG2u5zAeIYwUa0GV4b9DDMOC8gCfUdIS 1Dc+Q1HhMRRiIyXq7lnsNXo= =5Vq8 -----END PGP SIGNATURE----- --nextPart1563788.bnKDMgynq7--