From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Bruce Fields" Subject: Re: [Gluster-devel] regressions due to 64-bit ext4 directory cookies Date: Thu, 14 Feb 2013 16:47:44 -0500 Message-ID: <20130214214744.GC8343@fieldses.org> References: <20130213153654.GC17431@thunk.org> <20130213162059.GL14195@fieldses.org> <20130213222052.GD5938@thunk.org> <20130213224141.GU14195@fieldses.org> <20130213224720.GE5938@thunk.org> <20130213230511.GW14195@fieldses.org> <20130213234430.GF5938@thunk.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Theodore Ts'o , Bernd Schubert , sandeen-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, linux-nfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, gluster-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org To: Anand Avati Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-nfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-ext4.vger.kernel.org On Wed, Feb 13, 2013 at 04:05:01PM -0800, Anand Avati wrote: > On Wed, Feb 13, 2013 at 3:44 PM, Theodore Ts'o wrote: > > > > I suspect this would seriously screw over Gluster, though, and this > > wouldn't be a solution for NFSv3, since NFS needs long-lived directory > > cookies, and not the short-lived cookies which is all POSIX/SuSv3 > > guarantees. > > > > Actually this would work just fine with Gluster. Except in the case of > gluster-NFS, the native client is only acting like a router/proxy of > syscalls to the backend system. A directory opened by an application will > have a matching directory fd opened on ext4, and readdir from an app will > be translated into readdir on the matching fd on ext4. So the > app-on-glusterfs and glusterfsd-on-ext4 are essentially "moving in tandem". > As long as the offs^H^H^H^H cookies do not overflow in the transformation, > Gluster would not have a problem. > > However Gluster-NFS (and NFS in general, too) will break, as we > opendir/closedir potentially on every request. Yes. And, of course, NFS cookies live forever--we have no idea when a client will hand one back to us and expect us to do something with it. --b. -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html