Path: utzoo!attcan!uunet!mcvax!unido!laura!hmm
From: hmm@laura.UUCP (Hans-Martin Mosner)
Newsgroups: comp.lang.smalltalk
Subject: Re: Smalltalk-80 for '286
Keywords: Softsmarts, 286
Message-ID: <807@laura.UUCP>
Date: 20 Dec 88 22:39:22 GMT
References: <904@scubed.UUCP>
Reply-To: hmm@laura.UUCP (Hans-Martin Mosner)
Organization: University of Dortmund, W-Germany
Lines: 32

In article <904@scubed.UUCP> warner@s3snorkel.UUCP (Ken Warner) writes:
>ParcPlace...are you listening?  You have said that your stuff won't run on
>'286 boxes--how did Softsmarts do it?
As far as I know, they had a 16-bit system.  This means that you have an upper
limit on the number of objects (32 or 48 k, depends on SmallInteger range).
>I had a demo copy of Softsmarts
>Smalltalk-80 and it ran OK.  Not blazing fast, but acceptable.
Maybe, but you can forget about serious software development with a small
object space...
PPS has 32 bit object pointers, which means that the only limiting factor
for applications is the total amount of available memory, at least since
version 2.4 (2.3 and earlier have 24-bit memory addresses).  But it also means
that 16-bit machines like the 80x86 (x<3) are almost unusable for the system.
>
>I'll bet there are a lot of people that would really like a '286 version of
>PPS-80.  I know I would.
Sure.  And I would even more like it if it would run on my Casio wristwatch :-)
There are simply limits on the things you can do with such a machine.
The Smalltalk environment is demanding, and I think that burning CPU cycles
to provide a good user interface is basically a Good Thing to do.  But it means
that you can't do it on every machine...
The smallest machine to seriously use PPS Smalltalk-80
is a 8 Mhz 68000 with 4 Meg memory.  Our port to the Atari Mega ST does about
46 % Dorado (which is the fastest 68000 port around :-), and this is barely
enough.  A full port on a 12 MHz 80286 would probably be much slower...

	Hans-Martin
-- 
Hans-Martin Mosner		| Don't tell Borland about Smalltalk - |
hmm@unido.{uucp,bitnet}		| they might invent Turbo Smalltalk !  |
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