From owner-freebsd-geom@FreeBSD.ORG Tue Jun 20 08:43:51 2006 Return-Path: X-Original-To: freebsd-geom@freebsd.org Delivered-To: freebsd-geom@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5C73D16A47A; Tue, 20 Jun 2006 08:43:51 +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 B368243D53; Tue, 20 Jun 2006 08:43:50 +0000 (GMT) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id 52A9251388; Tue, 20 Jun 2006 10:43:49 +0200 (CEST) Received: from localhost (pjd.wheel.pl [10.0.1.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id 3C9E951307; Tue, 20 Jun 2006 10:43:44 +0200 (CEST) Date: Tue, 20 Jun 2006 10:41:10 +0200 From: Pawel Jakub Dawidek To: Brooks Davis Message-ID: <20060620084110.GC6235@garage.freebsd.pl> References: <20060619131101.GD1130@garage.freebsd.pl> <20060619185800.GA22546@odin.ac.hmc.edu> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="2/5bycvrmDh4d1IB" Content-Disposition: inline In-Reply-To: <20060619185800.GA22546@odin.ac.hmc.edu> 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=-5.9 required=3.0 tests=ALL_TRUSTED,BAYES_00 autolearn=ham version=3.0.4 Cc: freebsd-fs@freebsd.org, freebsd-current@freebsd.org, freebsd-geom@freebsd.org Subject: Re: Journaling UFS with gjournal. X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 Jun 2006 08:43:51 -0000 --2/5bycvrmDh4d1IB Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 19, 2006 at 11:58:00AM -0700, Brooks Davis wrote: +> On Mon, Jun 19, 2006 at 03:11:01PM +0200, Pawel Jakub Dawidek wrote: +> >=20 +> > How it works (in short). You may define one or two providers which +> > gjournal will use. If one provider is given, it will be used for both - +> > data and journal. If two providers are given, one will be used for data +> > and one for journal. +> > Every few seconds (you may define how many) journal is terminated and +> > marked as consistent and gjournal starts to copy data from it to the +> > data provider. In the same time new data are stored in new journal. +> > Let's call the moment in which journal is terminated as "journal switc= h". +>=20 +> Cool solution! I think I'll give this a try on my redundent mirror +> server at work. I'd be curious to see how gjournal performs with the +> journal on a battery backed ram disk like the gigabyte i-RAM: +>=20 +> http://www.giga-byte.com/Products/Storage/Products_Overview.aspx?Product= ID=3D2180&ProductName=3DGC-RAMDISK I am curious too:) But as I said, there is still a lot of room for performance improvements. The bottleneck currently is file system synchronization, I think. I hope our VFS gurus will look into VFS_SYNC() optimizations. --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --2/5bycvrmDh4d1IB Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (FreeBSD) iD8DBQFEl7SlForvXbEpPzQRAqB1AJ45J7spbBRtAcRzlA/ZhwzgNLz6PgCgmwRx y9ph5z7m5towyeZISTAnQik= =PdyB -----END PGP SIGNATURE----- --2/5bycvrmDh4d1IB--