> Are you folks on uni-processor or multi-processor machines?  
> I've been trying to cause a dual-core box to fall over, and have been 
> unable to so far... 

Uniprocessor.

>  cvs rdiff -r1.4 -r1.5 src/sys/kern/kern_turnstile.c

Nope.

> If the trace includes ufs_ihash* it would be good to see the output of
> "ps/l", and note if anything is sleeping on "tstile" if this happens again..
> The output of "show lock ufs_hashlock" would be useful here. If it shows
> that the lock is currently held, you can get a backtrace from the owner
> using "t/a <address of lwp>".

I'll try that when I get home.

As it happens, I can immediately cause it to happen within about
ten seconds by doing "find . -type d -print >/dev/null".