From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o9QMQE5x110219 for ; Tue, 26 Oct 2010 17:26:14 -0500 Received: from mailsrv14.zmi.at (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 3B369198F5C2 for ; Tue, 26 Oct 2010 15:27:29 -0700 (PDT) Received: from mailsrv14.zmi.at (mailsrv1.zmi.at [212.69.164.54]) by cuda.sgi.com with ESMTP id pXYhXD1NrOJ7cst7 for ; Tue, 26 Oct 2010 15:27:29 -0700 (PDT) Received: from mailsrv.i.zmi.at (h081217106033.dyn.cm.kabsi.at [81.217.106.33]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (Client CN "mailsrv2.i.zmi.at", Issuer "power4u.zmi.at" (not verified)) by mailsrv14.zmi.at (Postfix) with ESMTPSA id 0738117C for ; Wed, 27 Oct 2010 00:27:28 +0200 (CEST) Received: from saturn.localnet (saturn.i.zmi.at [10.72.27.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mailsrv.i.zmi.at (Postfix) with ESMTPSA id 1028B401C3D for ; Wed, 27 Oct 2010 00:27:27 +0200 (CEST) From: Michael Monnerie Subject: Re: XFS journaling position Date: Wed, 27 Oct 2010 00:27:26 +0200 References: <31c7e56286d37870011c17ee8e002760.squirrel@webmail.ics.forth.gr> <20101025161052.GC19425@sgi.com> In-Reply-To: <20101025161052.GC19425@sgi.com> MIME-Version: 1.0 Message-Id: <201010270027.26687@zmi.at> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============4137908418372290270==" Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com --===============4137908418372290270== Content-Type: multipart/signed; boundary="nextPart5805502.GqRqaSqsCg"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit --nextPart5805502.GqRqaSqsCg Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable On Montag, 25. Oktober 2010 Geoffrey Wehrman wrote: > I haven't found any documentation to support this, but I have been > told that the middle was selected for the single disk case to > minimize seek times. The distance the head must travel to or from > other locations on the disk is optimized by placing the log in the > middle of the disk. This is based on the assumption that 1) a disk is totally filled with data and 2) the partition that XFS resides on is the only one on the disk. =46or PCs or small servers you normally have a swap partition, the=20 recommended size is RAMx2 (at least it was once suggested, I've always=20 only set it to RAM size). Then you have at least a root filesystem,=20 which often won't be XFS, and then the data partition, which could be a=20 single partition until the end of the disk. For a single 300GB disk,=20 this means that around 20-50GB will be used by "other" (swap, root,=20 windows?) partitions, then maybe a single 250-280GB partition for XFS.=20 If you place the journal in the middle of the partition, you are already=20 in an area where disks are slower than on the outside. And if you fill=20 only half of the partition, it means your log is totally on the end of=20 the disk, access-wise. So for the average single-disk setup, wouldn't a log at 25%-35% of the=20 partition size be quicker than in the middle of the partition? Dave=20 Chinner just recently said that "a partition which is 85% filled is=20 full, from a filesystem view". That would already mean the log at 42% of=20 the partition size would be better. (Greetings to Douglas Adams, again=20 he was right ;-) Just my 2=A2, but I don't have a single disk machine with performance=20 needs. =2D-=20 mit freundlichen Gr=FCssen, Michael Monnerie, Ing. BSc it-management Internet Services http://proteger.at [gesprochen: Prot-e-schee] Tel: 0660 / 415 65 31 ****** Radiointerview zum Thema Spam ****** http://www.it-podcast.at/archiv.html#podcast-100716 // Wir haben im Moment zwei H=E4user zu verkaufen: // http://zmi.at/langegg/ // http://zmi.at/haus2009/ --nextPart5805502.GqRqaSqsCg Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (GNU/Linux) iEUEABECAAYFAkzHVc4ACgkQzhSR9xwSCbSMVACgs+musV+L5/novruk0GmOvr+h umQAmNCY2MsIrhOaGPiiCevGOI+sw+E= =EhJ7 -----END PGP SIGNATURE----- --nextPart5805502.GqRqaSqsCg-- --===============4137908418372290270== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs --===============4137908418372290270==--