From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753120AbXCMFKv (ORCPT ); Tue, 13 Mar 2007 01:10:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753129AbXCMFKu (ORCPT ); Tue, 13 Mar 2007 01:10:50 -0400 Received: from mail.gmx.net ([213.165.64.20]:48647 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753120AbXCMFKt (ORCPT ); Tue, 13 Mar 2007 01:10:49 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX18GPK9TF2AGgMuQ+SbNwH1xGlCBNKH1ol2v7cYQye M0eI7z3krSmfOZ Subject: Re: [PATCH][RSDL-mm 0/7] RSDL cpu scheduler for 2.6.21-rc3-mm2 From: Mike Galbraith To: Con Kolivas Cc: Ingo Molnar , linux kernel mailing list , ck list , Linus Torvalds , Andrew Morton In-Reply-To: <8cd998d50703121551u44ea3d85g2541503373f461f4@mail.gmail.com> References: <200703111457.17624.kernel@kolivas.org> <200703130549.47058.kernel@kolivas.org> <1173730314.6431.30.camel@Homer.simpson.net> <200703130738.19034.kernel@kolivas.org> <1173732344.6431.54.camel@Homer.simpson.net> <8cd998d50703121551u44ea3d85g2541503373f461f4@mail.gmail.com> Content-Type: text/plain Date: Tue, 13 Mar 2007 06:10:39 +0100 Message-Id: <1173762639.7944.45.camel@Homer.simpson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.8.2 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2007-03-13 at 09:51 +1100, Con Kolivas wrote: > On 13/03/07, Mike Galbraith wrote: > > As soon as your cpu is fully utilized, fairness looses or interactivity > > loses. Pick one. > > That's not true unless you refuse to prioritise your tasks > accordingly. Let's take this discussion in a different direction. You > already nice your lame processes. Why? You already have the concept > that you are prioritising things to normal or background tasks. You > say so yourself that lame is a background task. Stating the bleedingly > obvious, the unix way of prioritising things is via nice. You already > do that. So moving on from that... Sure. If a user wants to do anything interactive, they can indeed nice 19 the rest of their box before they start. > Your test case you ask "how can I maximise cpu usage". Well you know > the answer already. You run two threads. I won't dispute that. > > The debate seems to be centered on whether two tasks that are niced +5 > or to a higher value is background. In my opinion, nice 5 is not > background, but relatively less cpu. You already are savvy enough to > be using two threads and nicing them. All I ask you to do when using > RSDL is to change your expectations slightly and your settings from > nice 5 to nice 10 or 15 or even 19. Why is that so offensive to you? It's not "offensive" to me, it is a behavioral regression. The situation as we speak is that you can run cpu intensive tasks while watching eye-candy. With RSDL, you can't, you feel the non-interactive load instantly. Doesn't the fact that you're asking me to lower my expectations tell you that I just might have a point? > Please don't pick 5.none of the above. Please try to work with me on this. I'm not trying to be pig-headed. I'm of the opinion that fairness is great... until you strictly enforce it wrt interactive tasks. -Mike