From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-we0-f174.google.com ([74.125.82.174]:49981 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755725Ab2FGKgv (ORCPT ); Thu, 7 Jun 2012 06:36:51 -0400 Received: by weyu7 with SMTP id u7so256799wey.19 for ; Thu, 07 Jun 2012 03:36:50 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <4FD07F7D.6070509@panasas.com> References: <4FD06290.7050004@panasas.com> <4FD07F7D.6070509@panasas.com> Date: Thu, 7 Jun 2012 19:36:50 +0900 Message-ID: Subject: =?UTF-8?Q?Re=3A_=5BProblem=5DNFS_Server_=E2=80=93_Umount_results_in_Device?= =?UTF-8?Q?_Busy=2E?= From: Namjae Jeon To: Boaz Harrosh Cc: "J. Bruce Fields" , "Trond.Myklebust@netapp.com" , Amit Sahrawat , "linux-nfs@vger.kernel.org" , Namjae Jeon Content-Type: text/plain; charset=UTF-8 Sender: linux-nfs-owner@vger.kernel.org List-ID: 2012/6/7, Boaz Harrosh : > On 06/07/2012 12:43 PM, Namjae Jeon wrote: > >> 2012/6/7, Boaz Harrosh : >>> On 06/07/2012 10:47 AM, Namjae Jeon wrote: >>> >>>> Hi Bruce, Trond. >>>> >>>> As you know, Currently umount results in busy on NFS server although >>>> user tried to succeed to umount on NFS client. >>>> I suggest to add umount procedure to avoid umount busy issue. >>>> When calling umount on NFS client, The resources(exportfs entries >>>> cache) of mount point will be flushed on NFS server. and umount will >>>> be succeed without busy issue. >>>> >>>> how do you think about this suggestion ? >>>> >>> >>> >>> I second this request, what is needed so when all clients unmounted, >>> the system comes back to the sate it was before any clients have >>> mounted. i.e filesystems is not referenced and may unmount cleanly. >>> (This also happens with >= 4.0 clients only, so no excuses) >>> >>> This is a real problem for me, on Fedora machines. Because I export >>> iscsi devices which are network devices, and in the shutdown procedure >>> for some reason the "service nfs stop" of the server is much much to >>> late. the original umount of exofs (-o _netdev) fails because it's >>> held by NFSD, the iscsi devices go away regardless, and when nfsd >>> finally releases exofs, it gets deadlocked on some error handling. >>> OK I know I must fix the stuck-ness, but the problem will remain. >>> The FS will not unmount cleanly because it will only attempt >>> an unmount after its devices are gone. This will be solved if >>> nfsd would release its hold on the FS when all clients are gone. >>> >>> It was on my TODO to fix this for a long time, but I seem to be >>> too busy with more urgent matters. (What's the point of fixing the >>> shutdown if the steady state doesn't work yet) >>> >>> If someone has investigated the matter and knows what to do I would >>> appreciate any insights, and/or patches would be wonderful ;-) >> Hi Boaz. >> Oh.. You also are facing same problem. >> Actually I almost finish to imprement the patch about umount busy >> issue on NFS server. But I want to know Maintainer's opinion before >> posting. >> Thanks. > > > Please post it (maybe as RFC) I want to see it Okay, I will soon. > > Thanks > Boaz > >>> >>>> Thanks. >>>> >>> >>> <> >>> >>> Thanks >>> Boaz >>> >>> > > >