From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yuri D'Elia Subject: Re: Question on subvolumes and mount options Date: Mon, 14 Feb 2011 12:40:33 +0100 Message-ID: <20110214124033.13993f8d.wavexx@users.sf.net> References: <87oc6fj30p.fsf@savara.sat.thregr.org> <20110213173059.GB5484@carfax.org.uk> <87ei7bj03d.fsf@savara.sat.thregr.org> <20110213191820.GA6321@carfax.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII To: linux-btrfs@vger.kernel.org Return-path: List-ID: On Sun, 13 Feb 2011 19:18:20 +0000 Hugo Mills wrote: > Yes, it's the same piece of storage, just appearing at more than > one point in your overall filesystem. Similar to the way that bind > mounts work. I've noticed that I can also rename subvolumes as well using mv(1). Can I move/re-arrange subvolumes between them simply using mv? Does a move between subvolumes involve a copy? > > So you would recommend creating both /root and /home subvolumes, to be > > mounted separately, or create /root and /root/home subvolumes? > > The former. Thanks. I can see why this is clearly more flexible in the long term. > > What if I remount the /home subvol into /home2. What happens when I > > touch a file through /home (nodatasum) and what happens when I use > > /home2 - since both are available at the same time? > > They'll stay in sync with respect to the files written to either > one. I'm not sure what the behaviour of nodatasum is with different > mounts of the same subvolume. Can we get an exact answer/behavior for that? :) I mean, can I mount two different subvolumes in the same file system with different flags (such as ssd, nodatasum, compress)?