Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 5 Oct 2001 05:13:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 5 Oct 2001 05:12:57 -0400 Received: from mail.scs.ch ([212.254.229.5]:13745 "EHLO mail.scs.ch") by vger.kernel.org with ESMTP id ; Fri, 5 Oct 2001 05:12:52 -0400 Message-ID: <3BBD7B07.1B030E3D@scs.ch> Date: Fri, 05 Oct 2001 11:19:03 +0200 From: Reto Baettig X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.2.19 i686) X-Accept-Language: en MIME-Version: 1.0 To: Linux Kernel Mailinglist CC: petal.scs@scs.ch Subject: RAW I/O Performance Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi We are using RedHat's 2.4.3-12 kernel for our Alpha machines and stumbled over a bad performance problem with raw devices: Our test results (with a couple of disks and controllers ;-) were: Kernel 2.2.18 ~200MB/s 95% idle Kernel 2.4.3-12(RH) ~105MB/s 0% idle Kernel 2.4.11-pre3 ~173MB/s 28% idle The 2.2.18 kernel is using the SGI raw device patches. I saw that Andrea had a patch for 2.4.3aa where he could improve the RAW I/O performance significantly. I looked at the patch and I could not apply it to 2.4.3-12 because of conflicts which I was not able to resolve. I also looked at 2.4.10 and saw that Andreas patch was not in there. How can I get a similar RAW-IO performance with 2.4.3-12 as I had with 2.2.18? TIA Reto - 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/