From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1766876AbXDSQzW (ORCPT ); Thu, 19 Apr 2007 12:55:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1766877AbXDSQzW (ORCPT ); Thu, 19 Apr 2007 12:55:22 -0400 Received: from x35.xmailserver.org ([64.71.152.41]:2153 "EHLO x35.xmailserver.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1766876AbXDSQzU (ORCPT ); Thu, 19 Apr 2007 12:55:20 -0400 X-AuthUser: davidel@xmailserver.org Date: Thu, 19 Apr 2007 09:55:04 -0700 (PDT) From: Davide Libenzi X-X-Sender: davide@alien.or.mcafeemobile.com To: Mike Galbraith cc: Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS] In-Reply-To: <1176967937.6408.81.camel@Homer.simpson.net> Message-ID: References: <20070418055525.GS11115@waste.org> <20070418152355.GU11115@waste.org> <20070418174945.GA7930@elte.hu> <20070418175936.GA11980@elte.hu> <20070418214816.GA10902@elte.hu> <1176965560.6408.60.camel@Homer.simpson.net> <20070419070921.GA28528@elte.hu> <1176967937.6408.81.camel@Homer.simpson.net> X-GPG-FINGRPRINT: CFAE 5BEE FD36 F65E E640 56FE 0974 BF23 270F 474E X-GPG-PUBLIC_KEY: http://www.xmailserver.org/davidel.asc MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 19 Apr 2007, Mike Galbraith wrote: > On Thu, 2007-04-19 at 09:09 +0200, Ingo Molnar wrote: > > * Mike Galbraith wrote: > > > > > With a heavily reniced X (perfectly fine), that should indeed solve my > > > daily usage pattern nicely (always need godmode for shells, but not > > > for mozilla and ilk. 50/50 split automatic without renice of entire > > > gui) > > > > how about the first-approximation solution i suggested in the previous > > mail: to add a per UID default nice level? (With this default defaulting > > to '-10' for all root-owned processes, and defaulting to '0' for > > everything else.) That would solve most of the current CFS regressions > > at hand. > > That would make my kernel builds etc interfere with my other self's > surfing and whatnot. With it by EUID, when I'm surfing or whatnot, the > X portion of my Joe-User activity pushes the compile portion of root > down in bandwidth utilization automagically, which is exactly the right > thing, because the root me in not as important as the Joe-User me using > the GUI at that time. If the idea of X disturbing root upsets some, > they can move X to another UID. Generally, it seems perfect for here. Now guys, I did not follow the whole lengthy and feisty thread, but IIRC Con's scheduler has been attacked because, among other argouments, was requiring X to be reniced. This happened like a month ago IINM. I did not have time to look at Con's scheduler, and I only had a brief look at Ingo's one (looks very promising IMO, but so was the initial O(1) post before all the corner-cases fixes went in). But this is not a about technical merit, this is about applying the same rules of judgement to others as well to ourselves. We went from a "renicing X to -10 is bad because the scheduler should be able to correctly handle the problem w/out additional external plugs" to a totally opposite "let's renice -10 X, the whole SCHED_NORMAL kthreads class, on top of all the tasks owned by root" [1]. >>From a spectator POV like myself in this case, this looks rather "unfair". [1] I think, before and now, that that's more a duck tape patch than a real solution. OTOH if the "solution" is gonna be another maze of macros and heuristics filled with pretty bad corner cases, I may prefer the former. - Davide