🚀 go-pugleaf

In article <3v38dg$gpv@nnrp1.primenet.com>, english@primenet.com (Lawson
English) wrote:

> Define "too much." The Mac, when it first shipped, could barely run a 
> single app in the memory space provided. It already did a software-based 
> form of virtual memory using CODE resources and the Segment Manager.
> 
> 
> I think that you really don't understand how little space was left for an 
> application AND its data structures to run in.

Perhaps to put this in context, someone should look up how little RAM the
original Xerox PARC designs (Alto, Star) had. I thinky you may be
surprised at how little they used. I haven't dug up the specs on the Alto,
but the Star was launched with a minimum of 384K of RAM and a 10M local
disk. If this sounds like a lot compared with what the Mac had initially,
it's instructive to observe that the Star had a lot more in common with
Apple's Copland (possibly even the later Gershwin) system in terms of
system architecture, than with the original 1298K Mac. The Star's
document-centric architecture is a prototype for OpenDoc, used a 16-bit
character set for non-Roman alphabets, and had highly integrated
networking support.

Interestingly, in a fairly comprehensive article, I couldn't find anything
about pre-emption or protection.

The major reason for the failure of the Star as a commercial product was
probably price: it started at $16,500. Later price drops didn't save it,
so maybe marketing was also a problem.

Further reading:

J Johnson et al. The Xerox Star: A Retrospective, Computer, vol.  22 no.
9, September 1989, pp 11-26.
-- 
Philip Machanick                   philip@cs.wits.ac.za
Department of Computer Science, University of the Witwatersrand
2050 Wits, South Africa
phone 27(11)716-3309  fax 27(11)339-7965