From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Mon, 14 Aug 2006 07:31:40 -0700 (PDT) Received: from alnrmhc11.comcast.net (alnrmhc14.comcast.net [206.18.177.54]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id k7EEVUDW009282 for ; Mon, 14 Aug 2006 07:31:30 -0700 Message-ID: <44E07AC6.6000104@comcast.net> Date: Mon, 14 Aug 2006 09:29:42 -0400 From: Brian Davis MIME-Version: 1.0 Subject: Re: Negligible improvement when using su/sw for hardware RAID5, expected? References: <44DD46A5.7010308@comcast.net> <1155545494.1238.11.camel@donner.tecosim.de> In-Reply-To: <1155545494.1238.11.camel@donner.tecosim.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: xfs-bounce@oss.sgi.com Errors-To: xfs-bounce@oss.sgi.com List-Id: xfs To: utz lehmann Cc: xfs@oss.sgi.com I'll admit to being ignorant here....all I did was created the Linux partition with fdisk and then created the fs on top of that. Was there something else that needed to be done? Thanks, Brian utz lehmann wrote: > Hi > > You are using a partition. Is it correctly aligned? Usually the first > partition starts at sector 63. Which is in the middle of your stripe. > Use the whole disk (/dev/sda) or align the start of the partition to a > multiple of the stripe size. > But i doubt you will see a performance improvement with such a simple > test (single threaded sequential read/ write). > > > utz > > On Fri, 2006-08-11 at 23:10 -0400, Brian Davis wrote: > >> Is this expected? I thought I would see more improvement when tweaking >> my su/sw values for hardware RAID 5. >> >> Details, 3x300GB drives, 3Ware 7506-4LP Hardware RAID 5 using a 64K >> stripe size (non-configurable on this card). >> >> FS creation and Bonnie++ results: >> >> Untweaked:---------------------------------------------------------------------- >> >> >> localhost / # mkfs.xfs -f /dev/sda1 >> meta-data=/dev/sda1 isize=256 agcount=32, agsize=4578999 >> blks >> = sectsz=512 attr=0 >> data = bsize=4096 blocks=146527968, imaxpct=25 >> = sunit=0 swidth=0 blks, unwritten=1 >> naming =version 2 bsize=4096 >> log =internal log bsize=4096 blocks=32768, version=1 >> = sectsz=512 sunit=0 blks >> realtime =none extsz=65536 blocks=0, rtextents=0 >> localhost / # mount -t xfs /dev/sda1 /raid >> localhost / # cd /raid >> localhost raid # bonnie++ -n0 -u0 -r 768 -s 30720 -b -f >> Using uid:0, gid:0. >> Writing intelligently...done >> Rewriting...done >> Reading intelligently...done >> start 'em...done...done...done...done...done... >> Version 1.93c ------Sequential Output------ --Sequential Input- >> --Random- >> Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- >> --Seeks-- >> Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP >> /sec %CP >> localhost 30G 27722 40 23847 37 98367 99 >> 88.6 11 >> Latency 891ms 693ms 16968us >> 334ms >> >> Tweaked:------------------------------------------------------------------------- >> >> >> localhost / # mkfs.xfs -f -d sw=2,su=64k /dev/sda1 >> meta-data=/dev/sda1 isize=256 agcount=32, agsize=4578992 >> blks >> = sectsz=512 attr=0 >> data = bsize=4096 blocks=146527744, imaxpct=25 >> = sunit=16 swidth=32 blks, unwritten=1 >> naming =version 2 bsize=4096 >> log =internal log bsize=4096 blocks=32768, version=1 >> = sectsz=512 sunit=0 blks >> realtime =none extsz=65536 blocks=0, rtextents=0 >> localhost / # mount -t xfs /dev/sda1 /raid >> localhost / # cd /raid >> localhost raid # bonnie++ -n0 -u0 -r 768 -s 30720 -b -f >> Using uid:0, gid:0. >> Writing intelligently...done >> Rewriting...done >> Reading intelligently...done >> start 'em...done...done...done...done...done... >> Version 1.93c ------Sequential Output------ --Sequential Input- >> --Random- >> Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- >> --Seeks-- >> Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP >> /sec %CP >> localhost 30G 27938 43 23880 40 98066 99 >> 91.8 9 >> Latency 772ms 584ms 19889us >> 340ms >> >>