Re: octave in multiprocessor cpu

[Thomas Ilnseher]

Am Freitag, den 08.01.2010, 14:57 +0100 schrieb Carlo Sartori:
> Hi tom.
> Thank for your fast answer!
> 
> I looking for a way to lot the CPU usage in all my core, now when I
> start a octave program i seen in htop only one cpu running at 100% and
> the other 7 are at 0%. 

> Normally I don't use big matrices but long
> cycle "for".
This is VERY inperformant in Octave, as the for loop is evaluated by the
interpreter over and over again. The commercial alternative is better in
this regard, as it uses a dynamic recompiler.

But also Matlab can't help you with utilizing multiple cores when you
program your code like this. 

To get more performance you should at first try to 'vectorize' your
code.
>  I take a look about the libraries you have write in your
> answer, but if it is only for matrices operation it isn't what I need.
> I try to use google but i don't fount a simple way for make what I want.
> Sorry for my bad English.
> Carlo
> 
> 2010/1/8 Thomas Ilnseher <address@hidden>:
> > Am Freitag, den 08.01.2010, 14:35 +0100 schrieb Carlo Sartori:
> >>
> >> Hi
> >> I like to know if octave can use multiprocessor cpu. I have a Intel i7
> >> 720 CPU, Ubuntu see the 8 core correctly (4 real core with double
> >> processing for each one) but octave use only one at time. For me it is
> >> like if I have a cpu with only 800 MHz.
> > No the cpu will still run with it's specified clock speed.
> >
> > I'm not 100% sure, but octave uses lapack, blas, fftw and all that
> > stuff? maybe you can get a version of these libraries that automatically
> > exploit multiple cores for large matrices.
> >
> > Google should help. Also, I want to know if I totally misunderstood
> > something and write crap.
> >
> > -tom
> > --
> > Thomas Ilnseher <address@hidden>
> >
> >
> 
> 

-- 
Thomas Ilnseher <address@hidden>