Subject: Re: hangs with NFS
To: Izumi Tsutsui <tsutsui@ceres.dti.ne.jp>
From: Manuel Bouyer <bouyer@antioche.lip6.fr>
List: current-users
Date: 03/28/2001 20:22:12
On Thu, Mar 29, 2001 at 03:16:39AM +0900, Izumi Tsutsui wrote:
> In <20010328194947.A4993@antioche.eu.org>
> bouyer@antioche.lip6.fr wrote:
> 
> > with recent -current kernels I experience strange hangs when NFS is used.
> > NFS server is a NetBSD 1.5, client -current as of today. My home dir is on
> > the server.
>  :
> > Anyone else seen this ?
> 
> I'm annoyed by the same problem, too.
> 
> My server is NetBSD/arm32 1.5S (CATS) and
> NetBSD/hp300 1.5S and NetBSD/newsmips 1.5S hang
> when they try to read files on the NFS server.
> 
> news68k, i386, pmax and macppc (they are also 1.5S) do not
> have the problem, and 1.5.1_ALPHA i386 also hangs on access to
> 1.5S i386 server. Before upgrading server to 1.5S from 1.5,
> there was no problem, so I guess it is not client problem.
> 
> According to tcpdump output, it seems that the server replies to
> the clients' request, but clients do not response it at all.
> 
> 15:12:02.066040 192.168.20.100.1154638077 > 192.168.20.1.2049: 112 read [|nfs]
> 15:12:02.066477 192.168.20.1.2049 > 192.168.20.100.1154638077: reply ok 1472 read (frag 58869:1480@0+)
> 15:12:02.066524 192.168.20.1 > 192.168.20.100: (frag 58869:1480@1480+)
> 15:12:02.066535 192.168.20.1 > 192.168.20.100: (frag 58869:1480@2960+)
> 15:12:02.066544 192.168.20.1 > 192.168.20.100: (frag 58869:1480@4440+)
> 15:12:02.066917 192.168.20.1 > 192.168.20.100: (frag 58869:1480@5920+)
> 15:12:02.066926 192.168.20.1 > 192.168.20.100: (frag 58869:900@7400)

It's possible that in your case the client it dropping fragments (too slow,
maybe). Try reducing rsize (e.g. mount -o -r=496)

In my case, after more investigations, I think it's a lock not properly
relased in an error path, or something like that ...

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
--