Re: NetBSD/vax compiler bounty?

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> Actually, P0 is 1G, and I would expect that if more virtual memory is
> needed it could be allocated from P1 (although quite unorthodox...)

It could even be allocated from system space, though it would
significantly increase the cost of process switching.

> Max virtual memory (for userspace) on a vax is 2G.

3G - you're forgetting system space.  At least, unless you're using
"userspace" to mean "VM space designed for user/super/exec use" rather
than "VM space usable by user/super/exec mode".

Actually, 3G minus a little over 16M; you need system virtual space for
P0/P1 page tables, plus a tiny bit to trampoline off of to enter the
system.  System space is not normally used for userland, in large part
because the hardware provides no assist for context-switching it, but
it theoretically could be.

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