FreeBSD & Polygraph: Spontaneous reboots

Hi All,
I have a problem with our polygraph setup at the moment. We're trying to
test a device supplied to us by a competitor. The device's performance
has been pretty poor so far, at 75 requests/sec hit response times are
>750 millis so I have been trying to get a run to go at 30 requests/sec.


Obviously, this means the fill phase lasts a very long time. I have made
four attempts so far, and each time the client machine has spontaneously
rebooted between 10-30hours into testing. 

Nothing gets written to /var/log/messages and the console logs from
polyclt look completely normal (we had a simillar problem a while ago,
but only when massive numbers of transactions were failing and the
machines actually ran out of memory).

We are using The Measurement Factory edition of FreeBSD 4.3 on the
client/server nodes with polygraph 2.7.6. Would it be worth trying 2.8.0
as a first step?

I'm not the most experienced BSD admin, so I am at a bit of a loss as to
what steps to take to try and work out what is causing this. I've done a
complete hardware swap-out, as there did seem to be a problem with the
existing node but I still see the same behaviour.

Any suggestions would be most welcome. 

Cheers,

Bryn.

--
Bryn M. Reeves
TCS Associate, Research & Development Team.
Avantis Limited, http://www.avantisworld.com/