Return-Path: Received: from mail-out2.uio.no ([129.240.10.58]:51773 "EHLO mail-out2.uio.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754631Ab0BSTTU (ORCPT ); Fri, 19 Feb 2010 14:19:20 -0500 Subject: Re: NFSv4 From: Trond Myklebust To: "J.A." =?ISO-8859-1?Q?Magall=F3n?= Cc: LKML , linux-nfs@vger.kernel.org In-Reply-To: <20100219012322.3d323794@werewolf.home> References: <20100219012322.3d323794@werewolf.home> Content-Type: text/plain; charset="UTF-8" Date: Fri, 19 Feb 2010 11:19:14 -0800 Message-ID: <1266607154.3526.30.camel@localhost> Sender: linux-nfs-owner@vger.kernel.org List-ID: MIME-Version: 1.0 On Fri, 2010-02-19 at 01:23 +0100, J.A. Magallón wrote: > Hi all... > > First of all, kudos for new nfs-utils. Now, nfs4 works automagically and > like a charm. > > And now the hard part, some questions: > > - I have read that nfs4 includes in the server the locking protocol, no > need for separate lockd. But in my servers, it seems it is still running: > > root 2198 2 0 Feb18 ? 00:00:00 [nfsiod] > root 23501 2 0 01:01 ? 00:00:00 [nfsd4] > root 23502 2 0 01:01 ? 00:00:00 [nfsd] > root 23503 2 0 01:01 ? 00:00:00 [nfsd] > root 23504 2 0 01:01 ? 00:00:00 [nfsd] > root 23505 2 0 01:01 ? 00:00:00 [nfsd] > root 23506 2 0 01:01 ? 00:00:00 [nfsd] > root 23507 2 0 01:01 ? 00:00:00 [nfsd] > root 23508 2 0 01:01 ? 00:00:00 [nfsd] > root 23509 2 0 01:01 ? 00:00:00 [nfsd] > root 23500 2 0 01:01 ? 00:00:00 [lockd] > > Is there any problem with it ? I suppose (correct me if I'm wrong) > that this kernel lockd will only serve for v2 or v3 mounts, > that locking for client nfs4 mounts will go through nfsd4. > Is that right ? No. The client NFSv4 traffic goes through the ordinary 'nfsd' daemons. There is no special locking manager for NFSv4, since POSIX locks are part of the ordinary protocol. I don't think that the NFS server will switch off lockd even if you do specify that you only want to serve NFSv4. > - Why is there only 1 instance of v4 daemon ? The 'nfsd4' thread above is actually a workqueue that is used for garbage-cleaning expired NFSv4 state. It isn't a server thread. > - Is there any page describing the advantages of v4 ? I will have to > convince the department admin to activate v4 in his solaris boxen...;) One place to start is the NFSv4 design considerations. See http://tools.ietf.org/html/rfc2624 Cheers Trond