From owner-freebsd-stable@FreeBSD.ORG Thu Jan 11 20:02:01 2007 Return-Path: X-Original-To: freebsd-stable@freebsd.org Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id A0FD616A53C for ; Thu, 11 Jan 2007 20:01:59 +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 7075B13C44B for ; Thu, 11 Jan 2007 20:01:55 +0000 (UTC) (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 4F2B51A4D89; Thu, 11 Jan 2007 12:01:55 -0800 (PST) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id 99C1E51341; Thu, 11 Jan 2007 15:01:52 -0500 (EST) Date: Thu, 11 Jan 2007 15:01:52 -0500 From: Kris Kennaway To: Scott Oertel Message-ID: <20070111200152.GA36123@xor.obsecurity.org> References: <459ABB40.7050603@digiware.nl> <20070111153651.GC31382@xor.obsecurity.org> <45A68F2E.6040205@scottevil.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="45Z9DzgjV8m4Oswq" Content-Disposition: inline In-Reply-To: <45A68F2E.6040205@scottevil.com> User-Agent: Mutt/1.4.2.2i Cc: Willem Jan Withagen , freebsd-stable@freebsd.org, Kris Kennaway Subject: Re: running mksnap_ffs X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Jan 2007 20:02:01 -0000 --45Z9DzgjV8m4Oswq Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Jan 11, 2007 at 11:25:34AM -0800, Scott Oertel wrote: > Kris Kennaway wrote: > >On Tue, Jan 02, 2007 at 09:06:24PM +0100, Willem Jan Withagen wrote: > > =20 > >>Hi, > >> > >>I got the following Filesystem: > >>Filesystem Size Used Avail Capacity iused ifree %iused=20 > >>/dev/da0a 1.3T 422G 823G 34% 565952 182833470 0% > >> > >>Running of a 3ware 9550, on a dual core Opteron 242 with 1Gb. > >>The system is used as SMB/NFS server for my other systems here. > >> > >>I would like to make weekly snapshots, but manually running mksnap_ffs= =20 > >>freezes access to the disk (I sort of expected that) but the process=20 > >>never terminates. So I let is sit overnight, but looking a gstat did no= t=20 > >>reveil any activity what so ever... > >>The disk was not released, mksnap_ffs could not be terminated. > >>And things resulted in me rebooting the system. > >> > >>So: > >> - How long should I expect making a snapshot to take: > >> 5, 15, 30min, 1, 2 hour or even more??? > >> =20 > > > >Yes :) Snapshots were not designed for use in this way (they were > >designed to support background fsck and allow faster system recovery > >after power failure), so they don't scale as well as you might like on > >large filesystems. > > > >Kris > > =20 >=20 >=20 > If snapshots were designed to support background fsck, then why did they= =20 > not make it more scalable? If you can't create a snapshot without the=20 > system locking up, that means fsck won't be able to either, making=20 > background fsck worthless for systems with large storage. locking up !=3D taking a long time to complete. You haven't differentiated between those two situations yet. Kris --45Z9DzgjV8m4Oswq Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.1 (FreeBSD) iD8DBQFFppevWry0BWjoQKURAkYVAJsHXqePtaxxb5L0E/cDFMqu/BtfowCeIptK ETU60kdVt08I7mCyCVsfAT4= =ultb -----END PGP SIGNATURE----- --45Z9DzgjV8m4Oswq--