From owner-cvs-all Tue Feb 22 13: 2:33 2000 Delivered-To: cvs-all@freebsd.org Received: from gidora.zeta.org.au (gidora.zeta.org.au [203.26.10.25]) by hub.freebsd.org (Postfix) with SMTP id 0A48C37B698 for ; Tue, 22 Feb 2000 13:02:25 -0800 (PST) (envelope-from bde@zeta.org.au) Received: (qmail 29312 invoked from network); 22 Feb 2000 21:02:20 -0000 Received: from bde.zeta.org.au (203.2.228.102) by gidora.zeta.org.au with SMTP; 22 Feb 2000 21:02:20 -0000 Date: Wed, 23 Feb 2000 08:02:16 +1100 (EST) From: Bruce Evans X-Sender: bde@alphplex.bde.org To: Alfred Perlstein Cc: Luoqi Chen , cvs-all@FreeBSD.org, cvs-committers@FreeBSD.org Subject: Re: cvs commit: src/sbin/mount mount.8 In-Reply-To: <20000222115057.A21720@fw.wintelcom.net> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk On Tue, 22 Feb 2000, Alfred Perlstein wrote: > * Luoqi Chen [000222 08:18] wrote: > > Even if we fixed this one, we are not sure if there isn't any other problem > > left that would compromise filesystem integrity (remember this part of the > > code is barely tested). I think a warning label is still warranted. > > I agree, although the old one was a bit hysterical, is this truthful > and complete: > > Downgrading a filesystem from read-write to read-only may cause ^ mount status > filesystem corruption and therefore should be avoided. > .Pp > It may take a few moments for a filesystem going from async to sync or ^^^^^^^ > noasync to become fully safe with regard to consistancy after the option ^^^^^^^^^^^ consistency > has been toggled. Delete "sync or". noasync != sync (sync gives synchronous data updates). The second paragraph is mostly FUD. I wouldn't add it. fs_flushfiles() should flush all delayed writes, and it seems to do so (it does a VOP_FSYNC(..., MNT_WAIT) to flush the metadata). Therefore, the filesystem should be safe when `mount -u -o noasync ...' returns. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message