On Sun, 01 Apr 2007 22:48:33 +0200
Johnny Billquist <bqt@softjar.se> wrote:

> George Harvey wrote:
[ snip ]
> > I think it is a transmit problem so I've tried reducing the NFS
> > write size to 2K and haven't had any lockups yet. However, I'm now
> > getting file corruption instead :( Building pkgtools/digest fails
> > with syntax errors during the configure stage, looking at the
> > configure file I see that it has chunks missing and is much shorter
> > than it should be. The same source, on the same server, builds with
> > no problems on my SGI Challenge S so I'm fairly confident that it's
> > not a bug on the server. I'll do some more investigating...
> 
> I also have file corruption issues, and I'm using a local disk, so 
> that's not NFS-related (if we're seeing the same thing that is).
> Some parts gets filled with NULs instead of the correct contents when 
> files are created.

Hmm, I have no problems with local disk (CQD-223 SCSI controller) but I
put a sniffer on my network tonight and I can see that I'm getting NFS
write packets with all NULLs instead of the expected data. This is with
a simple file copy of a 200K text file from local disk to NFS mount with
a 1K NFS write size. Looking at the destination file, it is the right
size but every other 4K block has been replaced with NULLs.

It looks like I may have two problems, large writes cause the Ethernet
connection to hang, this can be demonstrated using ttcp or even ftp so
isn't a NFS problem as such. Using smaller write sizes with NFS avoids
the lockups but causes file corruption instead, which does look like a
NFS problem.

George



> >>
> >>Ken Seefried wrote:
> >>
> >>>George Harvey writes:
> >>>
> >>>
> >>>>I'd
> >>>>particularly like to get NFS working, are there any
> >>>
> >>>patches/workrounds > that might help?
> >>>
> >>>
> >>>Not that I've got insight this particular problem, and this won't
> >>>get to  your root cause, but my personal first dirty trick to NFS
> >>>problems is to  reduce the NFS read and write block size to 4K, 2K
> >>>or 1K.  Might let you  limp along until you figure out what's
> >really >>wrong. Ken
> >>
> 
> -- 
> Johnny Billquist                  || "I'm on a bus
>                                    ||  on a psychedelic trip
> email: bqt@softjar.se             ||  Reading murder books
> pdp is alive!                     ||  tryin' to stay hip" - B. Idol
>