Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754766AbZJZHBV (ORCPT ); Mon, 26 Oct 2009 03:01:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754488AbZJZHBU (ORCPT ); Mon, 26 Oct 2009 03:01:20 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:57216 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754589AbZJZHBR (ORCPT ); Mon, 26 Oct 2009 03:01:17 -0400 Date: Mon, 26 Oct 2009 08:01:12 +0100 From: Ingo Molnar To: Mike Galbraith Cc: Arjan van de Ven , Peter Zijlstra , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] sched: Disable affine wakeups by default Message-ID: <20091026070112.GA14641@elte.hu> References: <1256492289.14241.40.camel@marge.simson.net> <20091025123319.2b76bf69@infradead.org> <1256508287.17306.14.camel@marge.simson.net> <1256522035.7356.19.camel@laptop> <1256531907.7117.31.camel@marge.simson.net> <20091025215225.05ac9ac9@infradead.org> <1256533734.7117.45.camel@marge.simson.net> <20091025223657.5ebc2857@infradead.org> <1256536078.7117.67.camel@marge.simson.net> <1256536660.8150.3.camel@marge.simson.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1256536660.8150.3.camel@marge.simson.net> User-Agent: Mutt/1.5.19 (2009-01-05) X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=none autolearn=no SpamAssassin version=3.2.5 _SUMMARY_ Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1007 Lines: 26 * Mike Galbraith wrote: > On Mon, 2009-10-26 at 06:47 +0100, Mike Galbraith wrote: > > On Sun, 2009-10-25 at 22:36 -0700, Arjan van de Ven wrote: > > > > if you're a multicore domain you better have a shared cache.. > > > that's what it should mean. If it does not we should fix that. > > > > Sounds reasonable to me. I'll go make explosions. > > (Actually, if multicode and sibling does indeed mean shared cache, no > arch tinkering should be necessary, just reset SD_WAKE_AFFINE when > degenerating should work fine. Only thing is multicore with > siblings.. and test test test) Correct. There's a few cpus where multicore means separate caches but all modern CPUs have shared caches for cores so we want to tune for that. Ingo -- 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/