From owner-freebsd-questions@FreeBSD.ORG Fri Sep 1 23:06:44 2006 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C3F8116A4E0 for ; Fri, 1 Sep 2006 23:06:44 +0000 (UTC) (envelope-from skylar@cs.earlham.edu) Received: from quark.cs.earlham.edu (cs.earlham.edu [159.28.230.3]) by mx1.FreeBSD.org (Postfix) with ESMTP id 23D2E43D53 for ; Fri, 1 Sep 2006 23:06:34 +0000 (GMT) (envelope-from skylar@cs.earlham.edu) Received: from [128.95.231.218] (angband.gs.washington.edu [128.95.231.218]) (authenticated bits=0) by quark.cs.earlham.edu (8.13.6/8.13.3) with ESMTP id k81N6S9P085538 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 1 Sep 2006 19:06:31 -0400 (EDT) (envelope-from skylar@cs.earlham.edu) X-Authentication-Warning: quark.cs.earlham.edu: Host angband.gs.washington.edu [128.95.231.218] claimed to be [128.95.231.218] Message-ID: <44F8BCD9.4090308@cs.earlham.edu> Date: Fri, 01 Sep 2006 16:06:01 -0700 From: Skylar Thompson Organization: Earlham College Computer Science Department User-Agent: Mail/News 1.5.0.5 (X11/20060728) MIME-Version: 1.0 To: Kris Kennaway References: <44F87733.2020405@squaretrade.com> <20060901213936.GA21561@xor.obsecurity.org> In-Reply-To: <20060901213936.GA21561@xor.obsecurity.org> X-Enigmail-Version: 0.94.0.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigCD531B859C686449051A59CB" X-Greylist: Sender succeded SMTP AUTH authentication, not delayed by milter-greylist-1.6 (quark.cs.earlham.edu [159.28.230.3]); Fri, 01 Sep 2006 19:06:31 -0400 (EDT) X-Virus-Scanned: ClamAV 0.88.2/1623/Wed Jul 26 18:35:11 2006 on quark.cs.earlham.edu X-Virus-Status: Clean X-Scanned-By: MIMEDefang 2.56 on 159.28.230.3 X-Spam-Status: No, score=-2.5 required=8.0 tests=AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on quark.cs.earlham.edu Cc: Paul Lathrop , freebsd-questions@freebsd.org Subject: Re: Snapshot performance X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: skylar@cs.earlham.edu List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Sep 2006 23:06:44 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigCD531B859C686449051A59CB Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Kris Kennaway wrote: > On Fri, Sep 01, 2006 at 11:08:51AM -0700, Paul Lathrop wrote: > =20 >> Hi all, >> >> We're working on deploying a new mail server on FreeBSD 6.1-STABLE. On= e >> of the major selling points was the ability to take filesystem snapsho= ts >> in order to make backups from a consistent filesystem on such a >> high-traffic system. Unfortunately, when I take a snapshot, performanc= e >> slows to a crawl - to the point where the system stops responding to >> network requests (ping, SMTP, etc.). Also, the snapshot takes 10-15 >> minutes to complete. >> >> Is this a typical situation? Will I need to schedule downtime for >> backups in spite of this nifty new feature? Am I doing something wrong= ? >> =20 > > Time depends on the size of the filesystem - but you are correct that > snapshots were not designed with performance in mind (rather, to speed > up booting after an unclean shutdown by removing the need to wait for > fsck). > > Kris > =20 Are there plans to improve performance of snapshots? Using the freebsd-snapshot port to link FS snapshots to the automounter is pretty nifty, but it does kill I/O performance while that's in progress as the OP mentioned. --=20 -- Skylar Thompson (skylar@cs.earlham.edu) -- http://www.cs.earlham.edu/~skylar/ --------------enigCD531B859C686449051A59CB Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.3 (SunOS) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFE+Lzbsc4yyULgN4YRAlRfAJ9dC5MnU1tfKdpYAMKY4U708h0xhACfSfVX warXVnGguE+QaDz/RdslstM= =f7U4 -----END PGP SIGNATURE----- --------------enigCD531B859C686449051A59CB--