[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

multics vs vax



I agree with JIM that if multics fits your needs, you should use it.
For those of you who already have a VAX, you may feel some reluctance
to use a unique "other" machine for algebraic manipulation.

The VAX 11/780 is, we have found, a decent machine for running Lisp
and macsyma.  Given that memory is cheap and getting cheaper, and that
this seems to be the most important resource to make Lisp (and lots
of other things) run faster, I think it will continue to get better.
We are buying VAX memory at about $7k/megabyte, I think.  Thus the
difference, for macsyma, between a small machine .5meg and a large
machine 4 meg is not much money.  (You can get 8 meg by buying an
expensive controller from DEC, or waiting for 64k chip memory boards).
We have not gone above 4 meg on any of our machines; 3 or 4 macsymas
are less of a load than lots of other things (3 or 4 CIFplots, 3 or 4 troffs).

I am reminded, however, of the argument I have made in the past with
owners of cdc7600's who wanted to run macsyma on it, and I argued that
the machine was unsuited to running lisp; they argued that since the
7600 was, to them, free, it was the most suitable machine.  Many
people no doubt feel that their VAX is free;  a few people feel that
multics is free.  (I don't mean to compare the 7600 with the Honeywell
machine directly)  Just that there are lots of other considerations
than merely technical (i.e. does it work?).