From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: with ECARTIS (v1.0.0; list xfs); Mon, 14 Aug 2006 02:56:42 -0700 (PDT) Received: from dmz.tecosim.de (dmz.tecosim.com [195.135.152.162]) by oss.sgi.com (8.12.10/8.12.10/SuSE Linux 0.7) with ESMTP id k7E9uRDW005996 for ; Mon, 14 Aug 2006 02:56:27 -0700 Subject: Re: Negligible improvement when using su/sw for hardware RAID5, expected? From: utz lehmann In-Reply-To: <44DD46A5.7010308@comcast.net> References: <44DD46A5.7010308@comcast.net> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-fuAbNIqoNHd6p7/e6F08" Date: Mon, 14 Aug 2006 10:51:34 +0200 Message-Id: <1155545494.1238.11.camel@donner.tecosim.de> Mime-Version: 1.0 Sender: xfs-bounce@oss.sgi.com Errors-To: xfs-bounce@oss.sgi.com List-Id: xfs To: Brian Davis Cc: xfs@oss.sgi.com --=-fuAbNIqoNHd6p7/e6F08 Content-Type: text/plain Content-Transfer-Encoding: quoted-printable 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=20 On Fri, 2006-08-11 at 23:10 -0400, Brian Davis wrote: > Is this expected? I thought I would see more improvement when tweaking=20 > my su/sw values for hardware RAID 5. >=20 > Details, 3x300GB drives, 3Ware 7506-4LP Hardware RAID 5 using a 64K=20 > stripe size (non-configurable on this card). >=20 > FS creation and Bonnie++ results: >=20 > Untweaked:---------------------------------------------------------------= -------=20 >=20 >=20 > localhost / # mkfs.xfs -f /dev/sda1 > meta-data=3D/dev/sda1 isize=3D256 agcount=3D32, agsize=3D= 4578999=20 > blks > =3D sectsz=3D512 attr=3D0 > data =3D bsize=3D4096 blocks=3D146527968, ima= xpct=3D25 > =3D sunit=3D0 swidth=3D0 blks, unwritt= en=3D1 > naming =3Dversion 2 bsize=3D4096 > log =3Dinternal log bsize=3D4096 blocks=3D32768, version= =3D1 > =3D sectsz=3D512 sunit=3D0 blks > realtime =3Dnone extsz=3D65536 blocks=3D0, rtextents= =3D0 > 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-=20 > --Random- > Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block--=20 > --Seeks-- > Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP=20= =20 > /sec %CP > localhost 30G 27722 40 23847 37 98367 99=20= =20 > 88.6 11 > Latency 891ms 693ms 16968us=20=20= =20=20=20 > 334ms >=20 > Tweaked:-----------------------------------------------------------------= --------=20 >=20 >=20 > localhost / # mkfs.xfs -f -d sw=3D2,su=3D64k /dev/sda1 > meta-data=3D/dev/sda1 isize=3D256 agcount=3D32, agsize=3D= 4578992=20 > blks > =3D sectsz=3D512 attr=3D0 > data =3D bsize=3D4096 blocks=3D146527744, ima= xpct=3D25 > =3D sunit=3D16 swidth=3D32 blks, unwrit= ten=3D1 > naming =3Dversion 2 bsize=3D4096 > log =3Dinternal log bsize=3D4096 blocks=3D32768, version= =3D1 > =3D sectsz=3D512 sunit=3D0 blks > realtime =3Dnone extsz=3D65536 blocks=3D0, rtextents= =3D0 > 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-=20 > --Random- > Concurrency 1 -Per Chr- --Block-- -Rewrite- -Per Chr- --Block--=20 > --Seeks-- > Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP=20= =20 > /sec %CP > localhost 30G 27938 43 23880 40 98066 99=20= =20 > 91.8 9 > Latency 772ms 584ms 19889us=20=20= =20=20=20 > 340ms >=20 --=20 <> utz lehmann <> <> u.lehmann@de.tecosim.com <> <> <> TECOSIM GmbH / IT <> <> +49(0)-6142-82720 <> http://www.tecosim.com/ --=-fuAbNIqoNHd6p7/e6F08 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQBE4DmW7OmPIkYy5+4RAsUpAKCAhrRtilHrKspv9qaSKCvKL6SwcQCfUig2 TGU7L3/8iIytRMflps/Ukoc= =txA+ -----END PGP SIGNATURE----- --=-fuAbNIqoNHd6p7/e6F08--