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From: "Jeffrey R. Carter" <spam.not.jrcarter@acm.not.spam.org>
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Subject: Re: question about tasks, multithreading and multi-cpu machines
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Date: 2006-03-17T19:42:17+00:00
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Maciej Sobczak wrote:
> 
> Consider a simple example of two long vectors that need to be added. In 
> the simplest case you do this:
> 
>    for I in Vector'Range loop
>       V3(I) := V1(I) + V2(I);
>    end loop;
> 
> and you're done.

No, in all cases you should do

V3 := V1 + V2;

with an appropriate definition of "+" (which may be similar to your example).

> Now, assume that you want to target dual-CPU machine and you *know* that 
> you could greatly benefit from making things in paraller.

Then this is part of your requirements, and should be reflected in your design 
and implementation.

Incidentally, the English word is "parallel".

The interesting problem is writing portable code that takes advantage of N 
processors (N = 1, 2, 3, ...), with N unknown until run time.

-- 
Jeff Carter
"The time has come to act, and act fast. I'm leaving."
Blazing Saddles
36