SUN vs Lisp machine hardware differences?

[David Vinayak Wallace <Gumby@mcc.com>]

I would think the most serious one is address space.  Here's why we have
think we have to use lisp machines from Symbolics.  Perhaps some sun
users can enlighten me on how they (the Sun machines, not the users) compare:

First, RAM:

 CYC, the system I'm working on, needs at least 4 mw to even run, and 6
 to be moderately comfortable.  I was dissapointed that under 7.1 I
 couldn't bring a machine up to even 8 mw (high memory above 7.5 was
 ignored.)  I think this limitation is going to become a real problem
 for us in the next year or so.
 
 Can some SUN experts tell me what the maximum addressible quantity of
 RAM is for the sun machines?  Please don't use "bytes" -- the pointer is
 a more reasonable measure of comparison.

Virtual address space:

 The (Symbolics) lisp machine has a 28-bit address space.  Right now we
 use about 50mw of address space, and figure that we can scale up without
 problems via larger disks when we need to.   Needless to say, an
 Exploder with its 25-bit address space is out of the question.
 
 What are the real sizes of the various sun address spaces?  Does the
 68000 have the same architectural problems as the vax which preclude
 anything but a small address space?

Oh yea, one more thing.  If you've ever had to write network code
you'll appreciate 1> The quality of Symbolics' code (don't laugh --
their competitors are even worse!) and 2> the fact that you don't have
to write with foreign-function interfaces and worry about unboxing
packets.

David

PS: Why does Symbolics sell memory in "bytes."?  They call a 2mw board a
    "8mby" one.  This just makes their prices appear outrageously high,
    since they're not counting the tag or ecc bits...