Re: Octave with multithreading BLAS

[Sergei Steshenko]

--- On Wed, 4/17/13, yuer <address@hidden> wrote:

> From: yuer <address@hidden>
> Subject: Octave with multithreading BLAS
> To: address@hidden
> Date: Wednesday, April 17, 2013, 10:45 PM
> Hi, I am newbie to Octave. Recently I
> compiled Octave 3.6.4 on cluster
> computer(4 CPUs, 80 threads) with ATLAS 3.10 and Openblas.
> Both work but it
> seems that dot product on matrix is only in single thread
> while cross
> product is working in multicores.  I don't know whether
> some libraries are
> not correctly linked. any comments? thanks.
>  
> 
> 
> 
> --
> View this message in context: 
> http://octave.1599824.n4.nabble.com/Octave-with-multithreading-BLAS-tp4652015.html
> Sent from the Octave - General mailing list archive at
> Nabble.com.
>

In ATLAS multithreaded and single threaded libraries are separate ones:

address@hidden:~> ls -ltr ~/AFSWD/install/atlas-3.10.1/lib/
total 38263
-rwxr-xr-x 1 qemu users 10632071 2013-02-09 03:09 libsatlas.so
-rwxr-xr-x 1 qemu users 10732389 2013-02-09 03:09 libtatlas.so
-rw-r--r-- 1 qemu users  8498854 2013-02-09 03:12 liblapack.a
-rw-r--r-- 1 qemu users   388354 2013-02-09 03:12 libcblas.a
-rw-r--r-- 1 qemu users  7436506 2013-02-09 03:12 libatlas.a
-rw-r--r-- 1 qemu users   468804 2013-02-09 03:12 libptf77blas.a
-rw-r--r-- 1 qemu users   388952 2013-02-09 03:12 libptcblas.a
-rw-r--r-- 1 qemu users   468408 2013-02-09 03:12 libf77blas.a
address@hidden:~>  
.

AFAIR libtatlas.so, libptf77blas.a, libptcblas.a are multithreaded.

Check ATLAS doucmentation - in my case 
/mnt/sdb8/sergei/AFSWD_debug/build/atlas-3.10.1/doc/atlas_install.pdf file, 
page 13, "3.4 Building dynamic/shared libraries".

You might need to massage Makefiles to ensure that threaded libraries are used.

Regards,
  Sergei.

Regards,
  Sergei.