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From: Charmed Snark <snark@cogeco.ca>
Newsgroups: comp.lang.ada
Subject: Re: Multicore problem
Date: Wed, 10 Mar 2010 18:00:26 +0000 (UTC)
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Anatoly Chernyshev expounded in news:095dc775-e214-4ccd-bf26-45ab27b3b277
@s36g2000prh.googlegroups.com:

> Thanks a lot to all responded. What is clear now is that the problem
> is rather complicated. I guess, I'd better be off with distributing
> the calculation over several PCs, with one task on each.

I was wondering about these issues in connection with
pthreads. I have a basic interpreter project
(https://sourceforge.net/projects/bdbbasic) where I
was considering implementing matrix operations in 
multiple threads. 

The net wisdom suggested that the thread startup 
cost was around 100usec as a general rule. However,
that appears to be only the beginning of important
considerations. ;-)

>From the related post here, it seems that the matrix 
might need to be huge to be of benefit. But even then,
as the cores and cache interact, this might not improve
performance.

Interesting stuff indeed. Then when you add this to
multiple platforms, a project designer really gets
his hands dirty..

Warren