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Subject: Re: GOTO BLAS and multiple threads
Date: Mon, 23 Feb 2009 23:46:02 +0000 (UTC)
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Well i tested goto blas with 32 bit machine and i really get poor results, following is some thing i observed : also posting some reasons for this observations:

1. GOTO BLAS  does not improved any performance on 32 bit machine
Well from the group i came to know that, its mainly becoz my cache memory is less...

2. I will be  trying to compile GOTO BLAS on 64 bit machine with cache memory 8 times then the previous machine
:) will post results soon:

OK few questions it will be great if some one can reply

1. GOTO BLAS doesnot include FFT so it means that i cant use FFT Function in my code any more ........how can i use FFT in MATLAB programing while using GOTO BLAS
2. How much speed up is expected to increase in MATRIX-VECTOR Multiplication and Addition.
3. Is is possible to call MATLAB functions while using GOTO BLAS Library


 




"Akshay " <gulatiakshay@gmail.com> wrote in message <gmi1sd$df3$1@fred.mathworks.com>...
> But how to compile go to blas with matlab
> 
> Arne Schneck <arne.schneck@math.uni-karlsruhe.de> wrote in message <g7udqa$59s$1@news2.rz.uni-karlsruhe.de>...
> > Arne Schneck wrote:
> > > I've been trying to use GOTO BLAS instead of the BLAS implementation that
> > > comes with Matlab. The problem is that when I compile a C file (with mex)
> > > that uses one of the BLAS routines from the GOTO library (dsyrk in my
> > > case), it only uses 1 thread.
> > 
> > Okay, I kind of solved the problem, but something is still messed up. In
> > order to uses Goto's BLAS, I just set the BLAS_VERSION environment variable
> > to the Goto BLAS library. This makes Matlab commands like A*A' call the
> > BLAS subroutine from Goto's library instead of the ACML library. And it
> > apparently uses (at least) 8 threads. So that solves the issue for me.
> > 
> > But: When I link C MEX files against libgoto, the resulting MEX file shows
> > pretty random behavior which completely baffles me. In one Matlab session
> > it uses 8 threads (don't know for sure, but at least it's fast), then I
> > restart Matlab and it uses only 1 thread. Although nothing was changed. On
> > each restart of Matlab it randomly seems to choose whether to use 1 or 8
> > threads!
> > 
> > Anyone have any idea what's going on here?
> > 
> > Arne
> >