[R-sig-Debian] revolution mkl with R 3.01 on Ubuntu 13.04

[Michael Rutter]

On 07/18/2013 10:33 PM, Dirk Eddelbuettel wrote:
>
> On 18 July 2013 at 22:14, Elizabeth Tighe wrote:
> |
> | Dirk,  That worked! Sort of.  It's gone from running processes on one
> | processor to two processors and Rbenchmark ran in 64 seconds rather than
> | 178.  Is there a way to get it to use more than 2 processors when it
> | can?  (revo mkl used all available processors by default).
>
> That is by R's "design choice" as the parallel package sets the default to
> two.  See help(options), and/or the vignette for r-sig-hpc.
>
> There have been helpful discussion over on r-sig-hpc over the months; you
> probably want to lurk on that list / google-search its archives.
>

I am a little late to this thread, but I have an update.  Many moons 
ago, I filed a bug/request to get the openblas package to run on more 
than two threads.  Every once in a while, I would get an update to that 
request, and finally the said the had fixed that issue.  I added this to 
my "to do" pile, and I have finally gotten around to testing it.

And the good news is that it works.  If you go to my RDev PPA 
(https://launchpad.net/~marutter/+archive/rdev), you will find the 
latest version of Ubuntu's obenblas package backported to Raring, 
Quantal, and Precise.  You will also find updated versions of atlas and 
blas, as the new version of openblas breaks R if those are not installed 
as well.  I think Raring is fine, but Quantal and Precise need at least 
one installed.

If you install the libopenblas-base pacakge, it should work right out of 
the box.  On my quad core machine, it ran 4 threads without having to do 
anything besides installing the package.  R-benchmark-25.R went from 
20.1 to 16.6 seconds, but all cores were being used for the Matrix 
function part of the test.

Hope this helps,
Michael


-- 
Dr. Michael A. Rutter
School of Science
Penn State Erie, The Behrend College
4205 College Drive
Erie, PA 16563
http://math.bd.psu.edu/faculty/rutter
mar36 at psu.edu