From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 23 May 2002 01:44:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 23 May 2002 01:44:03 -0400 Received: from h24-67-14-151.cg.shawcable.net ([24.67.14.151]:56059 "EHLO webber.adilger.int") by vger.kernel.org with ESMTP id ; Thu, 23 May 2002 01:44:02 -0400 From: Andreas Dilger Date: Wed, 22 May 2002 23:42:19 -0600 To: Chris , linux-kernel@vger.kernel.org Subject: Re: It hurts when I shoot myself in the foot Message-ID: <20020523054219.GL458@turbolinux.com> Mail-Followup-To: Chris , linux-kernel@vger.kernel.org In-Reply-To: <200205221615.g4MGFCH30271@directcommunications.net> <20020523034821.GK458@turbolinux.com> <20020523044933.GB4006@matchmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.28i X-GPG-Key: 1024D/0D35BED6 X-GPG-Fingerprint: 7A37 5D79 BF1B CECA D44F 8A29 A488 39F5 0D35 BED6 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On May 22, 2002 21:49 -0700, Mike Fedyk wrote: > On Wed, May 22, 2002 at 09:48:21PM -0600, Andreas Dilger wrote: > > There was a kernel patch posted about 5 or so months ago which would > > "handle" this setup (CPUs with the same clock speed, but different > > multipliers). Alan Cox said it probably was a bad idea, so it wouldn't > > go into the kernel, but the patch may still be usable. > > > > This is sometimes called "asymmetric multiprocessing", and the thread > > is at http://marc.theaimsgroup.com/?l=linux-kernel&m=98519070331478&w=4 > > I thought asymmetric multiprocessing would support CPUs with different > speeds. ie, 400 & 450mhz. How would you get different multipliers and same > Mhz when the CPUs are on the same FSB(ignoring AMD SMP where each processor > has an exclusive FSB, and this might be possible)? That was what I was trying to say: same FSB speed * different multipliers = different CPU MHZ, like what the original poster is asking about. I don't think it is possible to configure a motherboard to have different FSB speeds for two processors. > There was a patch to compare the different features on the CPUs available > and use the subset available on all processors. Hmm, maybe if you had actually read my email and followed the URL I posted, you would have found the patch to which you refer ;-). Cheers, Andreas -- Andreas Dilger http://www-mddsp.enel.ucalgary.ca/People/adilger/ http://sourceforge.net/projects/ext2resize/