Date: Tue, 10 Sep 2013 16:35:30 -0400
To: Joschi Brauchle <joschi.brauchle@tum.de>
Cc: linux-nfs@vger.kernel.org
Subject: Re: nfsd4: utime sometimes takes 40+ seconds to return (but on
 SLES11SP3 with kernel 3.0.82)
Message-ID: <20130910203530.GA20296@fieldses.org>
References: <522F69A1.5090005@tum.de>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
In-Reply-To: <522F69A1.5090005@tum.de>
From: "J. Bruce Fields" <bfields@fieldses.org>
Sender: linux-nfs-owner@vger.kernel.org

On Tue, Sep 10, 2013 at 08:49:05PM +0200, Joschi Brauchle wrote:
> Hello everyone,
> 
> we are administrating an NFS high-availability cluster running on
> SLES11SP1 with kernel 2.6.32.59. Just recently, one of the cluster
> machines was updated to SLES11SP3 with kernel 3.0.82.
> 
> 
> We are now experiencing severe hangs on NFS clients when the
> SLES11SP3 server is running the NFS services. An strace on the
> hanging processes on the client side show that is is waiting up to
> 60+ seconds for a "utime()" call to complete.
> 
> 
> The problem we see is matching the problem described in the thread
> "v3.5 nfsd4 regression; utime sometimes takes 40+ seconds to
> return". If the NFS server is running on SLES11SP3, the little test
> program provided in this tread hangs at the "utime()" call for 60+
> seconds. It hangs each time it is run! It finishes right away with 0
> seconds delay is SLES11SP1 is providing NFS services, each time.
> 
> 
> Now, in the serverside logfiles of SLES11SP3 we see these messages
> (not so on SP1):
> --------------
> kernel: [99381.184976] RPC: AUTH_GSS upcall timed out.
> kernel: [99381.184978] Please check user daemon is running.
> --------------
> 
> We have always been running the NFS server without rpc.gssd on the
> server side, as the init script for the nfsserver also does not
> start rpc.gssd.
> 
> 
> Once we started rpc.gssd on the SLES11SP3 server, using the test
> utility on the client shows that the first call to "utime()"
> succeeds right away, the second call takes ~25s to complete. But
> now, any consecutive runs of the utility finish with no more delay.
> 
> 
> So can anyone confirm that with kernel 3.0+ the rpc.gssd daemon is
> also required on the server side for correct operation?
> 
> Has there been a change between kernel 2.6.32.59 and 3.0.x?
> 
> Thus, is the init script of the nfsserver in SLES11SP3 indeed
> missing to start rpc.gssd?

It should be starting rpc.gssd to allow callbacks, yes.

--b.