From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935825AbXGRSHr (ORCPT ); Wed, 18 Jul 2007 14:07:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759495AbXGRSHi (ORCPT ); Wed, 18 Jul 2007 14:07:38 -0400 Received: from wa-out-1112.google.com ([209.85.146.179]:19833 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754571AbXGRSHh (ORCPT ); Wed, 18 Jul 2007 14:07:37 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=FW9FnbYf9sUeS8a+42j9st03UWKIJjuK2/E36Pr2vESXBAmPDDHrxRZBI5CjVvw0NsjFIdNdP+3UP4MI0gClDMvHwGZX5DOu5fuWgyryZKSyU714AMs0RXcKCPpk8jf7godvZ1HMG429Jz19kZDTMai+dD4kxH4H3u06zEQeP5A= Message-ID: <64d833020707181107o705ff16ava129e91fcf68a8ef@mail.gmail.com> Date: Wed, 18 Jul 2007 14:07:36 -0400 From: koan To: "Rui Santos" Subject: Re: Slow Soft-RAID 5 performance Cc: linux-kernel@vger.kernel.org In-Reply-To: <469E4A70.1000306@grupopie.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <64d833020707180707i1bbbbcbao783e33a2487c9e2b@mail.gmail.com> <469E4A70.1000306@grupopie.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org 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. 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/ > > > > > > > >