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From: zenith@ensmp.fr (Steven Ericsson-Zenith)
Newsgroups: comp.parallel
Subject: parallel programming model
Message-ID: <12232@hubcap.clemson.edu>
Date: 13 Dec 90 12:49:02 GMT
Sender: fpst@hubcap.clemson.edu
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Approved: parallel@hubcap.clemson.edu


>A naive question:
>	We have two parallel programming models: shared memory model via
>shared variables and distributed memory model via message passing. 
>Is there any model which is some where between? Will it be more suitable
>for the persent comptuter architectures?

There is the Ease model which combines both and is efficient to
implement on machines of both architectures. For example, if you tried
to implement message passing on a shared memory machine you would suffer
a copy penalty - the reason many parallel programs appear to run slower
than expected :-). Implementing shared memory (single global space)
architecture over distributed memory machines is complicated by the
determination of locality.

Ease provides a solution which allows processes to interact via well
defined non-local spaces/scopes. The copy penalty is circumvented and
locality is clearly expressed.

Reference Yale University Research Report RR809, July 1990.
"Programming with Ease: a semiotic definition of the language"
by Steven Ericsson Zenith

Contact Chris Hatchell at Yale (hatchell@cs.yale.edu) for a copy or send
me your full address and I'll add you to the Ease mailing list. The Ease
Project is now located at Ecole des Mines de Paris.
--
Steven Ericsson Zenith * email: zenith@ensmp.fr *   fax: (1).64.69.47.09
                       |                        | voice: (1).64.69.48.52
	     Ecole Nationale Superieure des Mines de Paris
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