From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Sun, 16 Dec 2007 17:18:11 -0800 (PST) Received: from cuda.sgi.com (cuda1.sgi.com [192.48.168.28]) by oss.sgi.com (8.12.11.20060308/8.12.11/SuSE Linux 0.7) with ESMTP id lBH1I4na007464 for ; Sun, 16 Dec 2007 17:18:08 -0800 Received: from out3.smtp.messagingengine.com (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 376E81168A3B for ; Sun, 16 Dec 2007 17:18:16 -0800 (PST) Received: from out3.smtp.messagingengine.com (out3.smtp.messagingengine.com [66.111.4.27]) by cuda.sgi.com with ESMTP id jkE0M1118TCvpqOS for ; Sun, 16 Dec 2007 17:18:16 -0800 (PST) Received: from compute1.internal (compute1.internal [10.202.2.41]) by out1.messagingengine.com (Postfix) with ESMTP id C65F97DAA6 for ; Sun, 16 Dec 2007 20:17:44 -0500 (EST) Message-Id: <1197854264.9694.1226902133@webmail.messagingengine.com> From: "Alex Madarasz" Content-Disposition: inline Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="ISO-8859-1" MIME-Version: 1.0 References: <1197653927.3841.1226620089@webmail.messagingengine.com> <4764AB08.7040608@sandeen.net> Subject: Re: Fedora 8.0.1 XFS Tune on HW RAID for Max Write Throughput? In-Reply-To: <4764AB08.7040608@sandeen.net> Reply-To: List@madalexlists.nospammail.net Date: Sun, 16 Dec 2007 20:17:44 -0500 Sender: xfs-bounce@oss.sgi.com Errors-to: xfs-bounce@oss.sgi.com List-Id: xfs To: xfs@oss.sgi.com On Sat, 15 Dec 2007 22:35:20 -0600, "Eric Sandeen" said: > Alex Madarasz wrote: > > We're building a new Fedora 8.0.1 Linux system to stream data from a > > 250Msps ADC to disk, and want to start tuning the system > > configuration for maximum XFS write performance. To date, without > > any significant effort at tuning our Fedora 7 dev system, we're > > seeing 250MBps write with 8-bit samples and ~ 300MBps write with 16- > > bit samples. We want to push the tuning as far as we can go with > > this architecture before we start looking at other hardware options. > > Looking at various other tuning pages on the Web finds few that are > > interested in maxing out sequential writes to very large arrays > > while using SAS HW RAID with big fast SAS drives too. > ... > > > XFS Tuning Options? > > > > - HW RAID0: > > - Array/logical disk HW RAID stripe size? > > At any rate you'll want to match xfs's geometry with the raid > geometry. The HP P400 stripe size defaults to 128K and can go up to 256K (and down to 64K, 32K, ...). Any reason, with big sequential XFS write loads, I shouldn't just max it out at 256K and move on? I understand Linux XFS block size is limited to 4KiB max on Intel 32-bit architectures ... including PAE? > > - Cache enabled (some reports that cache s/b turned off?)? > > If it's battery-backed cache, leave it on, and disable barriers in xfs > (it's a mount option) It is indeed 512M of HP Battery-Backed Write Cache (BBWC). > > - xfs mkfs / mount options? > > David mentioned these before as a generic place to start: > > # mkfs.xfs -f -l lazy-count=1,version=2,size=128m -i attr=2 -d > # agcount=4 > > # mount -o logbsize=256k > > and that those would be upcoming new defaults for mkfs. > > 4 ags may not be what you want for a ~2T filesystem. > > - External Log? > > - How big a partition on the E200i? > > - mkfs / mount options? > > not sure if an external log would be beneficial or not.