Received: from localhost (unknown [200.46.204.183]) by postgresql.org (Postfix) with ESMTP id 29DD2650434 for ; Wed, 6 Aug 2008 21:03:33 -0300 (ADT) Received: from postgresql.org ([200.46.204.86]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 01783-02 for ; Wed, 6 Aug 2008 21:03:02 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from smtp4.clear.net.nz (smtp4.clear.net.nz [203.97.37.64]) by postgresql.org (Postfix) with ESMTP id 8C3CB650428 for ; Wed, 6 Aug 2008 21:02:10 -0300 (ADT) Received: from zmori.markir.net (121-73-163-60.dsl.telstraclear.net [121.73.163.60]) by smtp4.clear.net.nz (CLEAR Net Mail) with ESMTP id <0K5700G5XEREH930@smtp4.clear.net.nz> for pgsql-performance@postgresql.org; Thu, 07 Aug 2008 12:02:03 +1200 (NZST) Date: Thu, 07 Aug 2008 12:01:57 +1200 From: Mark Kirkwood Subject: Re: file system and raid performance In-reply-to: To: greg@tcscs.com Cc: 'Mark Wong' , david@lang.hm, pgsql-performance@postgresql.org, 'Gabrielle Roth' Message-id: <489A3B75.6060004@paradise.net.nz> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit References: <70c01d1d0808042154u7b78d988vac1e461a93b0ba10@mail.gmail.com> <70c01d1d0808050800j7196922bt2c4b43ba09a19099@mail.gmail.com> <4898E80A.3020809@paradise.net.nz> User-Agent: Thunderbird 2.0.0.14 (X11/20080724) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200808/21 X-Sequence-Number: 30902 Gregory S. Youngblood wrote: >> From: Mark Kirkwood [mailto:markir@paradise.net.nz] >> Mark Wong wrote: >> >>> On Mon, Aug 4, 2008 at 10:56 PM, Gregory S. Youngblood >>> >> wrote: >> >>>> I recently ran some tests on Ubuntu Hardy Server (Linux) comparing >>>> >> JFS, XFS, >> >>>> and ZFS+FUSE. It was all 32-bit and on old hardware, plus I only >>>> >> used >> >>>> bonnie++, so the numbers are really only useful for my hardware. >>>> >>>> What parameters were used to create the XFS partition in these >>>> >> tests? And, >> >>>> what options were used to mount the file system? Was the kernel 32- >>>> >> bit or >> >>>> 64-bit? Given what I've seen with some of the XFS options (like >>>> >> lazy-count), >> >>>> I am wondering about the options used in these tests. >>>> >>>> >>> The default (no arguments specified) parameters were used to create >>> the XFS partitions. Mount options specified are described in the >>> table. This was a 64-bit OS. >>> >>> >> I think it is a good idea to match the raid stripe size and give some >> indication of how many disks are in the array. E.g: >> >> For a 4 disk system with 256K stripe size I used: >> >> $ mkfs.xfs -d su=256k,sw=2 /dev/mdx >> >> which performed about 2-3 times quicker than the default (I did try >> sw=4 >> as well, but didn't notice any difference compared to sw=4). >> > > [Greg says] > I thought that xfs picked up those details when using md and a soft-raid > configuration. > > > > > > You are right, it does (I may be recalling performance from my other machine that has a 3Ware card - this was a couple of years ago...) Anyway, I'm thinking for the Hardware raid tests they may need to be specified. Cheers Mark