Re: nfs + Reiser4

[Trond Myklebust <trond.myklebust@fys.uio.no>]

On Wed, 2010-04-07 at 23:33 +0200, gg-B3jsHfKwJfLR7s880joybQ@public.gmane.org wrote: 
> Some more info on the machines in question.
> 
> server: gentoo linux 2.6.29 kernel patched for R4 
> .net-fs/nfs-utils-1.2.1  Recently added nfs4 to existing nfs3 in kernel. 
> This did not seem to improve/deteriorate the problem. This has been an 
> issue ever since I used nfs to remote boot the client.
> 
> Client. ARM SBC also running 2.6.29 nfs3. Similar issues seen when 
> running manufacturer's 2.4 kernel. Suggests problem is on server.
> 
> Redboot bootstrap loads kernel via http then boots with nfsroot supplied 
> by server.
> 
> All specific issues related here are as seen yesterday with both running 
> 2.6.29.
> 
> The set up is damn near unusable as it is behaving now . Files are 
> constantly out of sync. Changes seem to stay or disappear in a more or 
> less arbitrary fashion (ie no percievable repeatable pattern or cause). 
> Files often get some kind of merge state which is neither the state on 
> the server , nor the last saved state on the client.
> 
> /dev/root on / type nfs
> (rw,vers=2,rsize=4096,wsize=4096,namlen=255,hard,nointr,nolock,\proto=udp,timeo=\
> 11,retrans=3,sec=sys,addr=192.168.1.3)
> 
> I note vers=2 here, does this maybe indicate some trouble with the 
> initial negotiation and fallback to nfs2 ?
> 
> I don't have one clear , reproducible problem because the results are so 
> erratic. But just editting a file with vi on the client and reopening it 
> will give incorrect results 8 time out of 10.
> 
> The reboot issue killed me. I thought is desperation that that would at 
> least mean I got a clean copy.

OK, so clearly not a userspace NFS issue then.

Just out of interest, are you able to reproduce this problem with other
underlying filesystems? Reiser4 has never been merged into the mainline
kernel, so I doubt that any one of us has a test setup.

Cheers
  Trond