From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Serge E. Hallyn" Subject: Re: [C/R v20][PATCH 38/96] c/r: dump open file descriptors Date: Sun, 21 Mar 2010 14:40:19 -0500 Message-ID: <20100321194019.GA11714@hallyn.com> References: <1268960401-16680-1-git-send-email-orenl@cs.columbia.edu> <1268960401-16680-4-git-send-email-orenl@cs.columbia.edu> <20100320044310.GC2887@count0.beaverton.ibm.com> <20100321172703.GC4174@shareable.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Matt Helsley , linux-fsdevel@vger.kernel.org, Andreas Dilger , containers@lists.linux-foundation.org To: Jamie Lokier Return-path: Received: from hrndva-omtalb.mail.rr.com ([71.74.56.125]:48263 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751636Ab0CUTl0 (ORCPT ); Sun, 21 Mar 2010 15:41:26 -0400 Content-Disposition: inline In-Reply-To: <20100321172703.GC4174@shareable.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Quoting Jamie Lokier (jamie@shareable.org): > Matt Helsley wrote: > > > That said, if the intent is to allow the restore to be done on > > > another node with a "similar" filesystem (e.g. created by rsync/node > > > image), instead of having a coherent distributed filesystem on all > > > of the nodes then the filename makes sense. > > > > Yes, this is the intent. > > I would worry about programs which are using files which have been > deleted, renamed, or (very common) renamed-over by another process > after being opened, as there's a good chance they will successfully > open the wrong file after c/r, and corrupt state from then on. Userspace is expected to back up and restore the filesystem, for instance using a btrfs snapshot or a simple rsync or tar. If we detect anything which really is not supported (for instance inotify for now) then we fail and leave a log message explaining the failure. thanks, -serge