From owner-freebsd-questions@FreeBSD.ORG Fri Sep 1 21:39:39 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 C0DF216A4DA for ; Fri, 1 Sep 2006 21:39:39 +0000 (UTC) (envelope-from kris@obsecurity.org) Received: from elvis.mu.org (elvis.mu.org [192.203.228.196]) by mx1.FreeBSD.org (Postfix) with ESMTP id 84CB143D45 for ; Fri, 1 Sep 2006 21:39:39 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: from obsecurity.dyndns.org (elvis.mu.org [192.203.228.196]) by elvis.mu.org (Postfix) with ESMTP id 5DF091A3C1F; Fri, 1 Sep 2006 14:39:39 -0700 (PDT) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 1F2FA511E6; Fri, 1 Sep 2006 17:39:37 -0400 (EDT) Date: Fri, 1 Sep 2006 17:39:36 -0400 From: Kris Kennaway To: Paul Lathrop Message-ID: <20060901213936.GA21561@xor.obsecurity.org> References: <44F87733.2020405@squaretrade.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="HcAYCG3uE/tztfnV" Content-Disposition: inline In-Reply-To: <44F87733.2020405@squaretrade.com> User-Agent: Mutt/1.4.2.2i Cc: freebsd-questions@freebsd.org Subject: Re: Snapshot performance X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 01 Sep 2006 21:39:39 -0000 --HcAYCG3uE/tztfnV Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Sep 01, 2006 at 11:08:51AM -0700, Paul Lathrop wrote: > Hi all, >=20 > We're working on deploying a new mail server on FreeBSD 6.1-STABLE. One > of the major selling points was the ability to take filesystem snapshots > in order to make backups from a consistent filesystem on such a > high-traffic system. Unfortunately, when I take a snapshot, performance > 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. >=20 > 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? 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 --HcAYCG3uE/tztfnV Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQFE+KiYWry0BWjoQKURAoOEAJ4kJbh1mhuQtlbYLuxSkNQ6zEuoRACgvS1s iN/x3zmOsXzk89srDzOJJZ8= =q5Gf -----END PGP SIGNATURE----- --HcAYCG3uE/tztfnV--