Re: Octave and multicore processors

[Jaroslav Hajek]

On Thu, Mar 26, 2009 at 1:29 PM, Marcin Sleczka <address@hidden> wrote:
>
>
>
> Jaroslav Hajek-2 wrote:
>>
>> I'm curious: what makes you expect Octave should use two cores?
>>
> I thought that Octave will try to do this calculation as fast as he can.

Does all your other software always use all cores? I guess not.

> So he should use all processors (cores), but he uses only one. Is this normal
> that if I've got Mac Pro with 2 processors and 8 cores Octave will use only
> one? My caculations will take an hour instead 10 minutes (7 cores are on
> holiday? :-) Can I force them to work?

It depends on how you do your calculations. The only implicit
parallelism you can get in Octave right now is using a multithreaded
BLAS. Explicit parallelism can be achieved using some packages from
OctaveForge.
Some intrinsic functions may, and probably will, be easily
multithreaded, but I don't expect the interpreter to be multithreaded
anywhere in near future (unless, of course, you have a tip for funding
of such a project).


-- 
RNDr. Jaroslav Hajek
computing expert & GNU Octave developer
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz