Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S271329AbTHMCIP (ORCPT ); Tue, 12 Aug 2003 22:08:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S271331AbTHMCIP (ORCPT ); Tue, 12 Aug 2003 22:08:15 -0400 Received: from vladimir.pegasys.ws ([64.220.160.58]:27399 "EHLO vladimir.pegasys.ws") by vger.kernel.org with ESMTP id S271329AbTHMCIO (ORCPT ); Tue, 12 Aug 2003 22:08:14 -0400 Date: Tue, 12 Aug 2003 19:08:08 -0700 From: jw schultz To: linux kernel mailing list Subject: Re: [PATCH] O13int for interactivity Message-ID: <20030813020808.GC23237@pegasys.ws> Mail-Followup-To: jw schultz , linux kernel mailing list References: <200308050207.18096.kernel@kolivas.org> <200308120629.31476.rob@landley.net> <3F38CAC6.7010808@cyberone.com.au> <200308120735.04035.rob@landley.net> <3F38D64C.2030109@cyberone.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3F38D64C.2030109@cyberone.com.au> User-Agent: Mutt/1.3.27i X-Message-Flag: Reading this message may result in the loss of plausible deniability. Consult a lawyer to determine the extent of your liability Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1418 Lines: 32 On Tue, Aug 12, 2003 at 09:58:04PM +1000, Nick Piggin wrote: > I have been hearing of people complaining the scheduler is worse than > 2.4 so its not entirely obvious to me. But yeah lots of it is trial and > error, so I'm not saying Con is wasting his time. I've been watching Con and Ingo's efforts with the process scheduler and i haven't seen people complaining that the process scheduler is worse. They have complained that interactive processes seem to have more latency. Con has rightly questioned whether that might be because the process scheduler has less control over CPU time allocation than in 2.4. Remember that the process scheduler only manages the CPU time not spent in I/O and other overhead. If there is something in BIO chewing cycles it will wreak havoc with latency no matter what you do about process scheduling. The work on BIO to improve bandwidth and reduce latency was Herculean but the growing performance gap between CPU and I/O is a formidable challenge. -- ________________________________________________________________ J.W. Schultz Pegasystems Technologies email address: jw@pegasys.ws Remember Cernan and Schmitt - 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/