From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261909AbTLPUJt (ORCPT ); Tue, 16 Dec 2003 15:09:49 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262074AbTLPUJt (ORCPT ); Tue, 16 Dec 2003 15:09:49 -0500 Received: from pf138.torun.sdi.tpnet.pl ([213.76.207.138]:24079 "EHLO centaur.culm.net") by vger.kernel.org with ESMTP id S261909AbTLPUJs convert rfc822-to-8bit (ORCPT ); Tue, 16 Dec 2003 15:09:48 -0500 From: Witold Krecicki To: jw schultz , Linux Kernel Mailing List Subject: Re: raid0 slower than devices it is assembled of? Date: Tue, 16 Dec 2003 21:09:36 +0100 User-Agent: KMail/1.5.93 References: <200312151434.54886.adasi@kernel.pl> <20031216040156.GJ12726@pegasys.ws> In-Reply-To: <20031216040156.GJ12726@pegasys.ws> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 8BIT Message-Id: <200312162109.36672.adasi@kernel.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Dnia Tuesday 16 of December 2003 05:01, jw schultz napisa³: > No Linux [R]AID improves sequential performance. How would > reading 65KB from two disks in alternation be faster than > reading continuously from one disk? Well, but at the beginning I've got about 85-90MB/sec for buffered array reads. That was on 2.4.21-pre or even patched 2.4.20 (on siimage - in it's early stages, not sata_sil driver). Now it's 3 times slower (checkedwith preemptible kernel, it's even slower) - so something went bad. -- Witold Krêcicki (adasi) adasi [at] culm.net GPG key: 7AE20871 http://www.culm.net