Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758945AbXKCWin (ORCPT ); Sat, 3 Nov 2007 18:38:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755692AbXKCWig (ORCPT ); Sat, 3 Nov 2007 18:38:36 -0400 Received: from mail.acc.umu.se ([130.239.18.156]:32881 "EHLO mail.acc.umu.se" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754098AbXKCWif (ORCPT ); Sat, 3 Nov 2007 18:38:35 -0400 Date: Sat, 3 Nov 2007 23:38:24 +0100 (CET) From: =?ISO-8859-1?Q?Bo_Brant=E9n?= To: linux-kernel@vger.kernel.org cc: mpm@selenic.com Subject: Re: x86_64 ten times slower than i386 In-Reply-To: <20071103162640.GS17536@waste.org> Message-ID: References: <20071103162640.GS17536@waste.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 768 Lines: 16 On Sat, 3 Nov 2007, Matt Mackall wrote: > This is typically due to a problem with the setup of your MTRRs. Try > booting with mem=nnnM where nnn is some number smaller than your > actual amount of memory. Thank you for that advice, the system has 4GB and if I boot with mem=3072M it will run as fast as normal while if I don't use the mem option it will run 10 times slower, however if I use a figure like mem=3500M the kernel will panic, is there any way to determine the highest usable figure without try and error? - 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/