Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760868AbXF0Mjj (ORCPT ); Wed, 27 Jun 2007 08:39:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760677AbXF0Mj2 (ORCPT ); Wed, 27 Jun 2007 08:39:28 -0400 Received: from server145.whmcpanel.net ([69.72.254.178]:35933 "EHLO server459.whmcpanel.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1760375AbXF0Mj0 (ORCPT ); Wed, 27 Jun 2007 08:39:26 -0400 From: Alberto Gonzalez To: Kyle Moffett Subject: Re: Question about fair schedulers Date: Wed, 27 Jun 2007 14:39:20 +0200 User-Agent: KMail/1.9.7 Cc: Linux Kernel Mailing List References: <200706230007.15622.info@gnebu.es> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200706271439.21043.info@gnebu.es> X-PopBeforeSMTPSenders: info@gnebu.es X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - server459.whmcpanel.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - gnebu.es Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1526 Lines: 32 On Saturday 23 June 2007, Kyle Moffett wrote: > On Jun 22, 2007, at 18:07:15, Alberto Gonzalez wrote: > > P.S: As a second thought, a fair scheduler could behave really good > > in other scenarios, like a server running a busy forum on apache > > +mysql+php. Besides, this is a more real world scenario (and easier > > to benchmark). Why aren't people testing these schedulers under > > this kind of load? > > That kind of load is boring precisely because it doesn't care about > interactivity. CFS/SD aren't a whole lot different from mainline- > without-interactivity in that respect, precisely because the latency > of the network is between ten and a hundred times more than the > latency of the scheduler. The only time it really matters is with > desktops where users care about smoothness. Well, I've just seen some benchmarks of this kind with CFS and it does make a difference. The scalability problem with MySQL seems to get solved with this scheduler. However, the peak throughput is quite lower than with the same kernel/glibc version and mainline scheduler. http://jeffr-tech.livejournal.com/ Anyway, this kind of testing seems to be useful. Linux is too widely deployed in servers to ignore the behavior of a CPU scheduler in that scenario. Cheers, Alberto. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/