From owner-freebsd-hackers@FreeBSD.ORG Sat Aug 28 15:51:03 2010 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BA7F1106566B; Sat, 28 Aug 2010 15:51:03 +0000 (UTC) (envelope-from webmaster@kibab.com) Received: from mx0.deglitch.com (backbone.deglitch.com [78.110.53.255]) by mx1.freebsd.org (Postfix) with ESMTP id 74EBC8FC15; Sat, 28 Aug 2010 15:50:59 +0000 (UTC) Received: from localhost (89-178-223-44.broadband.corbina.ru [89.178.223.44]) by mx0.deglitch.com (Postfix) with ESMTPA id B54988FC53; Sat, 28 Aug 2010 19:50:27 +0400 (MSD) Date: Sat, 28 Aug 2010 19:50:24 +0400 From: Ilya Bakulin Message-ID: <20100828195024.3d671a76@kibab.com> In-Reply-To: <20100828130912.48205a47@kibab.com> References: <86wrry1hwv.fsf@ds4.des.no> <20100828130912.48205a47@kibab.com> Organization: Deglitch Networks X-Mailer: Claws Mail 3.7.6 (GTK+ 2.20.1; i386-portbld-freebsd8.0) Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/1tkeDJKIRhJAOzIOcxqbVjm"; protocol="application/pgp-signature" Cc: Dag-Erling =?utf-8?Q?Sm=C3=B8rgrav?= , hackers@freebsd.org, geom@freebsd.org Subject: Re: Support for WD Advanced Format disks X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 28 Aug 2010 15:51:03 -0000 --Sig_/1tkeDJKIRhJAOzIOcxqbVjm Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Sat, 28 Aug 2010 13:09:12 +0400 Ilya Bakulin wrote: > Right now I'm running phybs -w /dev/ad7p1 Well, phybs finished. Results: kibab-desktop# ./phybs -w /dev/ad7p1 count size offset step msec tps kBps 131072 1024 0 4096 3098125 0 42 131072 1024 512 4096 3100047 0 42 65536 2048 0 8192 1505809 0 87 65536 2048 512 8192 1505179 0 87 65536 2048 1024 8192 1506127 0 87 32768 4096 0 16384 1522343 1 86 32768 4096 512 16384 1521017 1 86 32768 4096 1024 16384 1523748 1 86 32768 4096 2048 16384 1522853 1 86 16384 8192 0 32768 890911 3 147 16384 8192 512 32768 892026 3 146 16384 8192 1024 32768 890699 3 147 16384 8192 2048 32768 891862 3 146 16384 8192 4096 32768 889903 3 147 Obviously 34-sectors offset is bad for phybs. Write requests are NEVER get = aligned. I have recreated partition as follows: kibab-desktop# gpart delete -i 1 ad7 ad7p1 deleted kibab-desktop# gpart add -t freebsd-ufs -s 10G -b 63 ad7 ad7p1 added kibab-desktop# gpart show ad7 =3D> 34 2930277101 ad7 GPT (1.4T) 34 29 - free - (15K) 63 20971520 1 freebsd-ufs (10G) 20971583 2909305552 - free - (1.4T) So, we have ad7p1 which is still misaligned, but if write request will star= t at offset=3D512, it will be aligned properly. Let's test as follows: kibab-desktop# ./phybs -l 4096 -w /dev/ad7p1 count size offset step msec tps kBps 32768 4096 0 16384 1520609 1 86 32768 4096 512 16384 17898 151 7323 32768 4096 1024 16384 1524899 1 85 :-) Aligned writes are 86 times faster than misaligned!!! --=20 Regards, Ilya Bakulin http://kibab.com xmpp://kibab612@jabber.ru --Sig_/1tkeDJKIRhJAOzIOcxqbVjm Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (FreeBSD) iEYEARECAAYFAkx5MEUACgkQo9vlj1oadwhRAACgqRCXTcKsfesxaMxPjO/Hs9E4 iV8AmwQWE3Gs0EHsyJj6CAtoq4QgbP2L =WxjB -----END PGP SIGNATURE----- --Sig_/1tkeDJKIRhJAOzIOcxqbVjm--