From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933326AbXGSLnS (ORCPT ); Thu, 19 Jul 2007 07:43:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755528AbXGSLnJ (ORCPT ); Thu, 19 Jul 2007 07:43:09 -0400 Received: from bipbip.grupopie.com ([195.23.16.24]:50081 "EHLO bipbip.grupopie.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756783AbXGSLnI (ORCPT ); Thu, 19 Jul 2007 07:43:08 -0400 Message-ID: <469F4E47.4020809@grupopie.com> Date: Thu, 19 Jul 2007 12:43:03 +0100 From: Rui Santos Organization: GrupoPIE, Portugal SA User-Agent: Thunderbird 2.0.0.4 (X11/20070613) MIME-Version: 1.0 To: koan CC: linux-kernel@vger.kernel.org Subject: Re: Slow Soft-RAID 5 performance References: <64d833020707180707i1bbbbcbao783e33a2487c9e2b@mail.gmail.com> <469E4A70.1000306@grupopie.com> <64d833020707181107o705ff16ava129e91fcf68a8ef@mail.gmail.com> In-Reply-To: <64d833020707181107o705ff16ava129e91fcf68a8ef@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org koan wrote: > Are you sure about that chunk size? In you initial posting you show > /proc/mdstat reporting: > > "md2 : active raid5 sdc3[2] sda3[0] sdb3[1] > 780083968 blocks level 5, 128k chunk, algorithm 2 [3/3] [UUU]" > > Which would seem to state a 128K chunk, and thus with a 4k block size > you would need a stride of 32. Hi Koan, Yes, I'm sure... Those 128K chunk was my initial setup, before the enlightenment from http://tldp.org/HOWTO/Software-RAID-HOWTO-5.html My reported test setup is by using 256K chunk. > > > > On 7/18/07, Rui Santos wrote: >> koan wrote: >> > How did you create the ext3 filesystem? >> >> The chunk_size is at 256KB, ext3 block size is 4k. I believe the correct >> option that should be passed trough to --stride is 64. >> Am I correct ? >> >> I've also tested ( after sending my first report ) with xfs. >> I've also increases readahead to 65535 on all HD's >> I've also increases the stripe_cache_size to 16384. >> >> I can now get ~100MB/sec... >> >> > >> > Did you use the appropriate --stride option as noted here: >> > http://tldp.org/HOWTO/Software-RAID-HOWTO-5.html (#5.11) >> > - >> > 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/ >> > >> > >> > >> >> > > >