Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752758AbYJaRiM (ORCPT ); Fri, 31 Oct 2008 13:38:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751571AbYJaRh5 (ORCPT ); Fri, 31 Oct 2008 13:37:57 -0400 Received: from mx2.redhat.com ([66.187.237.31]:53622 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751197AbYJaRh5 (ORCPT ); Fri, 31 Oct 2008 13:37:57 -0400 Date: Fri, 31 Oct 2008 13:37:37 -0400 From: Dave Jones To: Suresh Siddha , Peter Zijlstra , Linux Kernel , Ingo Molnar Subject: Re: sched domains oddness. Message-ID: <20081031173737.GA11443@redhat.com> Mail-Followup-To: Dave Jones , Suresh Siddha , Peter Zijlstra , Linux Kernel , Ingo Molnar References: <20081031162443.GA29885@redhat.com> <1225471911.7803.1596.camel@twins> <20081031170928.GB10468@linux-os.sc.intel.com> <20081031171721.GA8837@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20081031171721.GA8837@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2251 Lines: 73 On Fri, Oct 31, 2008 at 01:17:21PM -0400, Dave Jones wrote: > On Fri, Oct 31, 2008 at 10:09:29AM -0700, Suresh Siddha wrote: > > > > looks like someone is triggering rebuild_sched_domains(), is something > > > poking cpusetfs files or flipping between sched_mc settings? > > > > I remember someone mentioning that some distro's started setting > > sched_mc_power_savings to '1' by default during boot. On a dual-core > > laptop, this will not give any advantage. > > > > I have to fix the code to not export this tunable, when we have only > > socket in the system. > > > > Dave, Is your distro also setting this tunable blindly during boot :( > > (13:15:25:davej@vaio:~)$ cat /sys/devices/system/cpu/sched_mc_power_savings > 0 > > So no, unless something set it to 1, and then back to 0. > > A grep of etc shows up nothing in initscripts. Does hal or something > play with this? Even curiouser.. When I unplug AC and replug it, it happens again, but slightly differently.. CPU0 attaching NULL sched-domain. CPU1 attaching NULL sched-domain. CPU0 attaching sched-domain: domain 0: span 0-1 level MC groups: 0 1 domain 1: span 0-1 level CPU groups: 0-1 domain 2: span 0-1 level NODE groups: 0-1 CPU1 attaching sched-domain: domain 0: span 0-1 level MC groups: 1 0 domain 1: span 0-1 level CPU groups: 0-1 domain 2: span 0-1 level NODE groups: 0-1 CPU0 attaching NULL sched-domain. CPU1 attaching NULL sched-domain. CPU0 attaching sched-domain: domain 0: span 0-1 level MC groups: 0 1 domain 1: span 0-1 level NODE groups: 0-1 CPU1 attaching sched-domain: domain 0: span 0-1 level MC groups: 1 0 domain 1: span 0-1 level NODE groups: 0-1 Note how the CPU level doesn't show up in the 2nd case. This still doesn't explain the flip-flop I saw just from booting, as that was on AC the whole time. I grepped hal and gnome-power-manager, and didn't see anything touching sched_mc Dave -- http://www.codemonkey.org.uk -- 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/