Newsgroups: comp.parallel.mpi,comp.parallel.pvm
From: Kamran Karimi <kamran@wallybox.cei.net>
Subject: Re: Why explicit message passing??
Organization: World Lynx, Inc.
Date: Fri, 3 Apr 1998 01:39:30 +0000
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Message-ID: <Pine.LNX.3.96.980403013811.342A-100000@wallybox.cei.net>

Hi,

Bruce Scott TOK wrote:

>|>  In OOP you can hide the location of an object, allowing the programmer to
>|> use an object's services without bothering about its location. This is very
>|> good.
>
>Yes, but does the compiler understand?  And does the programmer have the
>ability to reach in and change a few things by hand when there is no
>speedup above 4 PEs?

 Yes. The compiler can understand. Later a Run Time System (or maybe the
OS itself) will manage things. The important point is, the programmer should
_not_ have to intervene.

 I agree that the current DSM or DOO technologies do not have enough
intelligence to do things optimally, so some programmers prefer to embed
their knowledge about the optimal program behaviour in the code (for example
by controling the size and the time of data exchanges) to speed things up.

 I hope things improve in the future. But the current technology can be
of use to some people.


-Kamran