From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752586AbZIHXii (ORCPT ); Tue, 8 Sep 2009 19:38:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752467AbZIHXih (ORCPT ); Tue, 8 Sep 2009 19:38:37 -0400 Received: from mail-in-14.arcor-online.net ([151.189.21.54]:46311 "EHLO mail-in-14.arcor-online.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752441AbZIHXig (ORCPT ); Tue, 8 Sep 2009 19:38:36 -0400 X-DKIM: Sendmail DKIM Filter v2.8.2 mail-in-16.arcor-online.net 283C2256D52 Message-ID: <4AA6EAFD.1090707@arcor.de> Date: Wed, 09 Sep 2009 02:38:37 +0300 From: Nikos Chantziaras Organization: Lucas Barks User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.1) Gecko/20090826 Thunderbird/3.0b3 MIME-Version: 1.0 To: Jiri Kosina CC: Juergen Beisert , linux-kernel@vger.kernel.org, Arjan van de Ven Subject: Re: BFS vs. mainline scheduler benchmarks and measurements References: <20090906205952.GA6516@elte.hu> <20090908013800.296a5fb5@infradead.org> <4AA62E4E.4040700@arcor.de> <200909081332.46129.jbe@pengutronix.de> <4AA6D40F.6040600@arcor.de> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/09/2009 02:20 AM, Jiri Kosina wrote: > On Wed, 9 Sep 2009, Nikos Chantziaras wrote: > >>>> Here the result: >>>> >>>> http://foss.math.aegean.gr/~realnc/pics/latop2.png >>>> >>>> Again: this is on an Intel Core 2 Duo CPU. >>> >>> Just an idea: Maybe some system management code hits you? >> >> I'm not sure what is meant with "system management code." > > System management interrupt happens when firmware/BIOS/HW-debugger is > executed in privilege mode so high, that even OS can't do anything about > that. > > It is used in many situations, such as > > - memory errors > - ACPI (mostly fan control) > - TPM > > OS has small to none possibility to influence SMI/SMM. But if this would > be the cause, you should probably obtain completely different results on > different hardware configuration (as it is likely to have completely > different SMM behavior). Wouldn't that mean that a BFS-patched kernel would suffer from this too? In any case, of the above, only fan control is active, and I've run with it disabled on occasion (hot summer days, I wanted to just keep it max with no fan control) with no change. As far as I can tell, the Asus P5E doesn't have a TPM (the "Deluxe" and "VM" models seem to have one.) As for memory errors, I use unbuffered non-ECC RAM which passes a memtest86+ cycle cleanly (well, at least the last time I ran it through one, a few months ago.)