From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264916AbTLWDRE (ORCPT ); Mon, 22 Dec 2003 22:17:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264934AbTLWDRE (ORCPT ); Mon, 22 Dec 2003 22:17:04 -0500 Received: from c211-28-147-198.thoms1.vic.optusnet.com.au ([211.28.147.198]:52687 "EHLO mail.kolivas.org") by vger.kernel.org with ESMTP id S264930AbTLWDRB (ORCPT ); Mon, 22 Dec 2003 22:17:01 -0500 From: Con Kolivas To: Nick Piggin Subject: Re: [PATCH] 2.6.0 batch scheduling, HT aware Date: Tue, 23 Dec 2003 14:16:58 +1100 User-Agent: KMail/1.5.3 Cc: "Nakajima, Jun" , linux kernel mailing list References: <200312231138.21734.kernel@kolivas.org> <3FE7AF24.40600@cyberone.com.au> <200312231415.38611.kernel@kolivas.org> In-Reply-To: <200312231415.38611.kernel@kolivas.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200312231416.58998.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Dec 2003 14:15, Con Kolivas wrote: > On Tue, 23 Dec 2003 13:57, Nick Piggin wrote: > > Con Kolivas wrote: > > >On Tue, 23 Dec 2003 12:36, Nick Piggin wrote: > > >>Con Kolivas wrote: > > >>>I discussed this with Ingo and that's the sort of thing we thought of. > > >>>Perhaps a relative crossover of 10 dynamic priorities and an absolute > > >>>crossover of 5 static priorities before things got queued together. > > >>> This is really only required for the UP HT case. > > >> > > >>Well I guess it would still be nice for "SMP HT" as well. Hopefully the > > >>code can be generic enough that it would just carry over nicely. > > > > > >I disagree. I can't think of a real world scenario where 2+ physical > > > cpus would benefit from this. > > > > Well its the same problem. A nice -20 process can still lose 40-55% of > > its performance to a nice 19 process, a figure of 10% is probably too > > high and we'd really want it <= 5% like what happens with a single > > logical processor. > > I changed my mind just after I sent that mail. 4 physical cores running > three nice 20 and one nice -20 task gives the nice -20 task only 25% of the > total cpu and 25% to each of the nice 20 tasks. Err that should read 4 logical cores. Con