From owner-freebsd-performance@FreeBSD.ORG Sat Nov 4 20:56:06 2006 Return-Path: X-Original-To: freebsd-performance@freebsd.org Delivered-To: freebsd-performance@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 359F016A403 for ; Sat, 4 Nov 2006 20:56:06 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (arm132.internetdsl.tpnet.pl [83.17.198.132]) by mx1.FreeBSD.org (Postfix) with ESMTP id 6245843D69 for ; Sat, 4 Nov 2006 20:55:57 +0000 (GMT) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id E091148803; Sat, 4 Nov 2006 21:55:54 +0100 (CET) Received: from localhost (dll2.neoplus.adsl.tpnet.pl [83.24.41.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id 2AA5C48800; Sat, 4 Nov 2006 21:55:48 +0100 (CET) Date: Sat, 4 Nov 2006 21:55:42 +0100 From: Pawel Jakub Dawidek To: Oles Hnatkevych Message-ID: <20061104205542.GB83118@garage.freebsd.pl> References: <184686318.20061104222857@able.com.ua> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ZoaI/ZTpAVc4A5k6" Content-Disposition: inline In-Reply-To: <184686318.20061104222857@able.com.ua> X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 7.0-CURRENT i386 User-Agent: mutt-ng/devel-r804 (FreeBSD) X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: ** X-Spam-Status: No, score=2.6 required=3.0 tests=BAYES_00,RCVD_IN_NJABL_DUL, RCVD_IN_SORBS_DUL,RCVD_IN_XBL autolearn=no version=3.0.4 Cc: freebsd-performance@freebsd.org Subject: Re: geom stripe perfomance question X-BeenThere: freebsd-performance@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Performance/tuning List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 04 Nov 2006 20:56:06 -0000 --ZoaI/ZTpAVc4A5k6 Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Nov 04, 2006 at 10:28:57PM +0200, Oles Hnatkevych wrote: > Hello all! >=20 > I wonder why geom stripe works much worse than the separate disks that > constitute stripe. >=20 > I have a stripe from two disks. Disks are on separate ATA channels. >=20 > root# gstripe list > Geom name: bigdata > State: UP > Status: Total=3D2, Online=3D2 > Type: AUTOMATIC > Stripesize: 262144 > ID: 4233231544 > Providers: > 1. Name: stripe/bigdata > Mediasize: 500118323200 (466G) > Sectorsize: 512 > Mode: r1w1e1 > Consumers: > 1. Name: ad1 > Mediasize: 250059350016 (233G) > Sectorsize: 512 > Mode: r1w1e2 > Number: 0 > 2. Name: ad2 > Mediasize: 250059350016 (233G) > Sectorsize: 512 > Mode: r1w1e2 > Number: 1 >=20 > Now let's read one of them and stripe. >=20 > root# dd if=3D/dev/ad1 of=3D/dev/null bs=3D1m count=3D1000 > 1000+0 records in > 1000+0 records out > 1048576000 bytes transferred in 14.579483 secs (71921343 bytes/sec) >=20 > root# dd if=3D/dev/stripe/bigdata of=3D/dev/null bs=3D1m count=3D1000 > 1000+0 records in > 1000+0 records out > 1048576000 bytes transferred in 15.882796 secs (66019610 bytes/sec) >=20 > What I would expect is doubling the speed of transfer, not > slowing down. Am I wrong? Or is geom_stripe inefficient? >=20 > I am running 6.2-PRERELEASE on Celeron 800. It should be, but first try something like: dd if=3D/dev/ad1 of=3D/dev/null bs=3D1m count=3D1000 &; dd if=3D/dev/ad2 of= =3D/dev/null bs=3D1m count=3D1000 & --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --ZoaI/ZTpAVc4A5k6 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.4 (FreeBSD) iD8DBQFFTP5OForvXbEpPzQRAhQXAKCsV/R15GqWtK57wItzNVsgK2MGLACgw57o oG5a8XnIkwlOaB1ftEBgdA4= =yDHV -----END PGP SIGNATURE----- --ZoaI/ZTpAVc4A5k6--