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From: yon@apollo.HP.COM (David Yon)
Newsgroups: comp.lang.smalltalk
Subject: ST-80 Processes and pre-emption
Message-ID: <49b89829.20b6d@apollo.HP.COM>
Date: 10 Apr 90 15:32:00 GMT
Sender: root@apollo.HP.COM
Reply-To: yon@apollo.HP.COM (David Yon)
Followup-To: comp.lang.smalltalk
Organization: Hewlett-Packard Apollo Division - Chelmsford, MA
Lines: 21


Hey there Smalltalk-80 hackers...

	I'm working on prototyping a system which requires us to explore
concurrency issues.  Our model is of a central messaging server connected
to several running tools.  The message server and each tool will probably
map one-to-one to a UNIX process in the final product.

	The problem is as follows.  We really, really want this thing to 
simulate the final environment as closely as possible.  One of the things
we want to simulate is each of these processes marching ahead using UNIX
the pre-emptive multitasking model.  In Smalltalk-80 (in 2.3 at least) 
multi-tasking is NOT preemptive.  A process has control until it explicitly
terminates or suspends.

	Seems to me that anyone who has had to use Smalltalk to simulate 
real-world events must have run up against this.  Any good/bad experiences
out there?  Thanks...

David Yon
Apollo Computer