[R-sig-hpc] Getting multithreaded R working (solution)

[Jonathan Greenberg]

I really like that all we have to do is "update-alternatives --install
/usr/lib/libblas.so.3gf" with your version -- gotoblas2 was a breeze
to get working this technique.  Mostly with MKL I'm just unclear on
what specific file I need to link against once its been installed.
Actually, along these lines, does LAPACK work independently from the
BLAS, e.g. will the "default" LAPACK (sudo apt-get install
liblapack-dev) use whichever BLAS happens to be linked up, or do we
need a different LAPACK (update-alternatives --config liblapack.so)
for each particularly BLAS we are using (e.g. use the GotoBLAS2 lapack
with GotoBLAS2, use Intel MKL's LAPACK, with Intel's BLAS, etc...)

And unfortunately no revolution-mkl for debian yet :(  The intel
install is easy tho, just run the install script and its all good.  I
did move it out of /opt tho and into /usr/lib to live with the rest of
the libraries on my system!

--j

On Thu, Jul 29, 2010 at 3:16 PM, Dirk Eddelbuettel <edd at debian.org> wrote:
>
> On 29 July 2010 at 23:46, Stefan Theussl wrote:
> | [...]
> |  > P.S. If anyone has *easy* instructions for getting atlas working as a
> |  > multithreaded library or how do drop in the Intel MKL (I couldn't
> |  > figure out which *.so would be the correct one) please let me know and
> |  > I'll post them as well.
> |
> | I did get MKL working with R via the following trick:
> |
> | 1) export
> | LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/intel/intel-mkl-9.0.018/lib/em64t
> |
> | 2) then configure with:
> | "--with-blas=-L/opt/intel/intel-mkl-9.0.018/lib/em64t/ -lmkl -lguide
> | -lpthread"
> |
> | Back then I used MKL version 9.0.018. I don't know if this still works
> | with more recent MKL or R.
>
> Step 2) should not be necessary.  The BLAS is a binary interface; you can
> "simply" drop the right ones in.  By having ld.so "find" the MKL ones before
> the system ones, we made the MKL be used in the Revolution R release with
> Ubuntu 9.10.  That still works for -- so no rebuilding of R needed here.
>
>
> On 29 July 2010 at 14:56, Jonathan Greenberg wrote:
> | Have you (or anyone) gotten Intel MKL working via the "plugin"
> | approach that Dirk has setup for the debian packages, where you just
> | point:
>
>
> I have :)
>
> I have a proof-of-concept shell script that takes advantage of the Debian /
> Ubuntu package management system and does the following for benchmarks:
>
>    i)    removes all accelerates blas and runs with 'refblas'
>
>    ii)   installs Atlas and runs with 'atlas'
>
>    iii)  removes Atlas, install MKL (via aforementioned Revo package) and
>          runs with 'mkl'
>
>    iv)   remove MKL and install goto (using .deb package built with the neat
>          goto-helper package from the ISM in Japan) and run 'goto'
>
> plus for kicks
>
>    v)    install gputools and runs with 'gpu'
>
> I showed first results in the 'Intro to HPC' tutorial at useR and want to do
> some more work on this.  In fact, the gputools authors and I have a mostly
> empty project on r-forge for this but not had time to do much...
>
>
>
> --
> Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com
>