Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752538AbXE3J3A (ORCPT ); Wed, 30 May 2007 05:29:00 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751376AbXE3J2w (ORCPT ); Wed, 30 May 2007 05:28:52 -0400 Received: from linux.dunaweb.hu ([62.77.196.1]:44414 "EHLO linux.dunaweb.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750888AbXE3J2v (ORCPT ); Wed, 30 May 2007 05:28:51 -0400 Message-ID: <465D43C0.60609@dunaweb.hu> Date: Wed, 30 May 2007 11:28:32 +0200 From: Zoltan Boszormenyi User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: linux-kernel , Justin Piszcz Subject: Re: Kernel 2.6.21.3 does not work with 8GB of RAM on Intel 965WH Content-Type: text/plain; charset=ISO-8859-2; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 936 Lines: 31 Hi, > Look at how slow the raid benchmarks are in dmesg with 8GB of memory! > > [ 59.592560] raid6: using algorithm sse2x4 (476 MB/s) > [ 59.597558] raid5: using function: generic_sse (56.000 MB/sec) > > Yikes! > > With mem=4096M: > [ 60.336352] raid6: using algorithm sse2x4 (6804 MB/s) > [ 60.341345] raid5: using function: generic_sse (8552.000 MB/sec) > > What is going on here? > > Justin. I saw a similar effect on a P5 board that could only cache 64MB of memory a long time ago. Putting more memory into it made the machine slower and e.g. made the sym2 driver giving up at initialization. Maybe it's a modern reincarnation of the problem? Best regards, Zolt?n B?sz?rm?nyi - 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/