This is just a report-to-the-community on this; if you didn't care
about my note of two weeks ago about SPARC crashes, you probably want
to skip this.

> Date: Tue, 13 Sep 1994 18:58:17 -0400

> Our SPARC running NetBSD has been crashing, reliably, every night.
> [...]

After some interesting and very helpful correspondence with cgd, this
has been solved.  I was using nullfs to clone a portion of the
filesystem tree that included special device nodes, and nullfs wasn't
handling this right.  The problem has been found and fixed (briefly: a
missing call to checkalias() that couldn't be inserted because of
locking), and I've seen the fixes to miscfs/nullfs/null_subr.c (and a
corresponding change to umapfs) show up in the tree supped from
sun-lamp, so I think it can be called closed.  Incidentally, my posted
guesses about vclean were thoroughly wide of the mark.

The reason it was crashing every night was simply that the problem
wasn't tickled until something accessed the nullfs-mounted devices,
which wasn't happening until a "find / ..." was run via a cron job.

					der Mouse

			    mouse@collatz.mcrcim.mcgill.edu