Primarily in order to support NFS paging and diskless operation, I've
installed a few VM improvements today, including the rediscovery of a
long-lost anti-deadlock mod from Paul Kranenburg.

This may well help in rare cases even when using the usual raw
partition pager.

It would be really nice if some of you running -current could verify
that nothing goes downhill with this change. I'm not too worried about
NFS and diskless, since that's certainly better than it was. I'm mainly
concerned that behavior is at least as good as before in the normal
(raw partition pager) case, so that the mods can safely be included in
a 1.3.1 patch release.

I guess I'll also accept results on NFS and diskless operation. Note that
you may need to run swapctl -A again in /etc/rc.local in order to pick up
NFS volumes; depending on the vintage of your /etc/rc NFS may not be up
when swap is normally configured. Also, do confirm that you really have
a swap configured by doing a "swapctl -l" prior to any tests!

Finally, before and after tests would be really nice, just so you can verify
for yourself that any problems you see weren't already there on your system
in the first place, and so I don't get blamed for preexisting hardware and
software bugs! :)

Thanks...

Ross Harvey
ross@teraflop.com