From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758255AbZBKRXY (ORCPT ); Wed, 11 Feb 2009 12:23:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755329AbZBKRXL (ORCPT ); Wed, 11 Feb 2009 12:23:11 -0500 Received: from fogou.chygwyn.com ([195.171.2.24]:55936 "EHLO fogou.chygwyn.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757313AbZBKRXK (ORCPT ); Wed, 11 Feb 2009 12:23:10 -0500 Date: Wed, 11 Feb 2009 17:18:16 +0000 From: steve@chygwyn.com To: Kirill Kuvaldin Cc: linux-cluster@redhat.com, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: GFS2 file locking issues Message-ID: <20090211171816.GA14516@fogou.chygwyn.com> References: <2d42915c0902110255k3c0741a9s6830765bce6be052@mail.gmail.com> <20090211133648.GA10273@fogou.chygwyn.com> <2d42915c0902110637o2c0a88c7h72b280b972a6162e@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2d42915c0902110637o2c0a88c7h72b280b972a6162e@mail.gmail.com> Organization: ChyGwyn Limited X-Registered-Office: Digital Technium, Singleton Park, Swansea. SA2 8PP User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Wed, Feb 11, 2009 at 05:37:11PM +0300, Kirill Kuvaldin wrote: > On Wed, Feb 11, 2009 at 4:36 PM, wrote: > > Hi, > > > > On Wed, Feb 11, 2009 at 01:55:08PM +0300, Kirill Kuvaldin wrote: > >> Hi, > >> > >> I'm trying to understand how the FS locking mechanism should work. > >> > >> I'm running a clustered GFS2 across two nodes, each node is a Xen domU. > >> To check if locking works correctly I wrote the simple perl script below. > >> Basically the script opens a file, locks it to prevent others from > >> writing into it, writes 20 lines into it, then unlocks and closes. > >>i > > > > It should be exactly the same on GFS and GFS2, after all the code for > > flock is almost identical between the two. What mount options did you > > use? > > No specific options used, just mount -t gfs2 /dev/gfsc/lvol0 /gfs2... > > > Which lock manager are you using - I presume lock_dlm? > > > > Yes, the FS was created using to be used with lock_dlm. I'm not sure > if it is actually used for GFS2. How can I check that? > > Kirill cat /proc/mounts It should be listed in the options. That will also tell you if localflocks has been set as well. We do know of a bug in the GFS/GFS2 flock code though, it ought to be using an interruptible wait and it doesn't at the moment. Otherwise I don't know of any other issues. Which kernel version are you using? Steve.