Start it up with a monitor and keyboard attached, so you can see any
errors it spits out.  It's likely that you'll see an error from the
ethernet driver about running out of buffer space (or something
similar), from when your process started swapping over NFS.  It
generates enough NFS traffic in a low-memory condition that the driver 
gets a bit fudged, and is unable to interact with the network to page
anything back in or back out.

But check it out for yourself - you may have a different problem.

(Keep meaning to report this one myself).

  -Dave

Lo and Behold, Ignatios Souvatzis said:
> Hello,
> 
> I am able to make my Sharks wedge nearly at will.
> 
> * start PVM on 8 of them.
> * start xmandel (an pvm application, that will distribute work to all 
>   configured PVM nodes)
> * wait...
> 
> repeat until one of the Sharks wedges.
> 
> Definition of "wedge":
> 
> - doesn't react to serial console any more, not even to a break.
> - doesn't react to network, especially: doesn't pong when you ping it.
> - the front LED is either steady green or steady off.
> - the inside yellow LEDs are steady on.
> - the inside green LED is happily blinking, as if it was connected to
>   network activity (is it?)
> 
> 
> Machine configuration:
> 
> - diskless
> - 64 MB of RAM.
> - 47 MB of NFS swap (apparently, not used at all)
> - /dev on mfs 
> - /tmp on mfs (but not used very much)
> 
> The 8 sharks are connected to a desktop Ethernet hub, which in turn is 
> connected to a catalyst switch which connects to the server.
> 
> The kernel can be netbsd-1.4: shark-netboot, or the same built with the
> fixed bcopyinout.S.
> 
> Any idea what to do to debug this?
> 
> Regards,
> 	Ignatios Souvatzis
> 
> 
> -- 
>  * Progress (n.): The process through which Usenet has evolved from
>    smart people in front of dumb terminals to dumb people in front of
>    smart terminals.  -- obs@burnout.demon.co.uk (obscurity)

-- 
work: danderse@cs.utah.edu                     me:  angio@pobox.com
      University of Utah                            http://www.angio.net/
      Computer Science - Flux Research Group   "What's footnote FIVE?"