From: Matt Bernstein <+systems.extlists.nfsv4-9gaWkGYbp/DQzY9nttDBhA@public.gmane.org> Subject: Re: Turning off delegations in NFSv4 server? Date: Fri, 5 Mar 2010 15:12:46 +0000 (GMT) Message-ID: References: <4786788D.6040707@garzik.org> <20080110200034.GI2132@fieldses.org> <20100304143317.GA17191@fieldses.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: Jeff Garzik , NFS list , nfsv4@linux-nfs.org, Matt Bernstein To: "J. Bruce Fields" Return-path: Received: from flan.dcs.qmul.ac.uk ([138.37.95.138]:36690 "EHLO mail.dcs.qmul.ac.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753138Ab0CEPMs (ORCPT ); Fri, 5 Mar 2010 10:12:48 -0500 In-Reply-To: <20100304143317.GA17191@fieldses.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mar 4 J. Bruce Fields wrote: > On Thu, Mar 04, 2010 at 09:23:26AM +0000, Matt Bernstein wrote: >> On Jan 10 2008 J. Bruce Fields wrote: >>> The easiest thing is probably just to turn off leases: >>> echo 0 >/proc/sys/fs/leases-enable >> >> I found this from two years ago, and am wondering >> - is this still the easiest thing to do? >> - is this on server, client or both? >> - will it break anything else? >> >> We have a CentOS 5.4 NFS3/NFS4/samba server with about 300 clients on its >> subnet, and another 100-200 on another subnet, which under high load has >> started kernel-panicking (sometimes in nfsd4_cb_recall). > > Have you filed a bug with the backtraces? Duly nudged. I've posted the most recent one to . >> I want to disable delegations to see if that cures our symptoms--but I >> worry that turning leases off might cause other problems. > > No, it shouldn't cause problems, at least for NFSv4 clients. (Samba may > be more reliant on leases, especially if Samba and NFSv4 clients are > acting on the same files at the same time--but I don't know.) Thanks; no-one's grumbled just yet. Matt