From: "per isakson" <poi1@kth2.se>
Path: news.mathworks.com!newsfeed-00.mathworks.com!webcrossing
Newsgroups: comp.soft-sys.matlab
Subject: Re: matlab on a dual core
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Date: Mon, 22 Jan 2007 13:26:00 -0500
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Matt wrote:
>
>
> I have a strange phenomenon occurring when using Matlab on a dual
> core Dell laptop machine. If I run two Matlab programs with two
> Matlab windows open at the same time, each of them runs much faster
> (2x or 3x) than if I run a single program with only one Matlab
> window
> open (or, two Matlab windows open but one program being idle). Has
> anybody encountered a similar problem?
  
I cannot reproduce your result with my two processor (Xeon) Dell
Workstation with WinXP + R2006b. On the contrary each process is
about ten percent slower when the other is running.

I used this code for the test:

function cssm( N )
    val = rand( 1e6, 1 );
    while true
        tic
        for n = 1:N
            s1 = sin(val);
        end
        toc
        drawnow
    end
end

/ per