R help - Jun 2010 - Compiling R with multi-threaded BLAS math libraries - why not actually ?

Hello all,
I came
across<http://www.r-bloggers.com/performance-benefits-of-linking-r-to-multithreaded-math-libraries/>
David
Smith's new post
Performance benefits of linking R to multithreaded math
libraries<http://blog.revolutionanalytics.com/2010/06/performance-benefits-of-multithreaded-r.html>
Which explains how (and why) REvolution distribution of R uses
different BLAS math libraries for R, so to
allow multi-threaded mathematical computation.
What the post doesn't explain is why it is that native R distribution
doesn't use the multi-threaded version of the libraries.  Is it because
R-devel team didn't get to it yet or is it for some technical reason.
Could someone please help to explain the situation?

Thanks in advance,
Tal

p.s: I wasn't sure if to send the question here or to R-devel, I decided to
send it here.  If I am in the wrong - please let me know.



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The reason that the BLAS libraries are not installed as part of the
standard distribution is that its desirable that the standard
distribution be the same on all machines whereas you need a different
BLAS library for each different CPU type.

In the case of REvolution R, David mentioned using the Intel MKL,
proprietary library which may not be distributed in the way R is
distributed. Maybe REvolution has a license to redistribute the library.
For the others, I suspect Gabor has the right idea, that the R-core team
would rather not keep architecture dependent code in the sources,
although there is a very small amount already (`grep -R __asm__`).

However, I know using Linux (Debian in particular) it is fairly
straightforward to build R with `enhanced' BLAS libraries. The R
Administration and Installation manual has a pretty good section on
linking with enhanced BLAS and LAPACK libs, including the Intel MKL, if
you are willing cough up $399, or swear not to use the library
commercially or academically.

Maybe a short tutorial using free software, such as ATLAS would be
suitable content for an r-bloggers post :) ?

Matt Shotwell
Graduate Student
Div. Biostatistics and Epidemiology
Medical University of South Carolina

On Fri, 2010-06-11 at 19:21 -0400, Tal Galili wrote:
> Hello all,
> I came
across<http://www.r-bloggers.com/performance-benefits-of-linking-r-to-multithreaded-math-libraries/>
> David
> Smith's new post
> Performance benefits of linking R to multithreaded math
>
libraries<http://blog.revolutionanalytics.com/2010/06/performance-benefits-of-multithreaded-r.html>
> Which explains how (and why) REvolution distribution of R uses
> different BLAS math libraries for R, so to
> allow multi-threaded mathematical computation.
> What the post doesn't explain is why it is that native R distribution
> doesn't use the multi-threaded version of the libraries.  Is it because
> R-devel team didn't get to it yet or is it for some technical reason.
> Could someone please help to explain the situation?
> 
> Thanks in advance,
> Tal
> 
> p.s: I wasn't sure if to send the question here or to R-devel, I
decided to
> send it here.  If I am in the wrong - please let me know.
> 
> 
> 
> ----------------Contact
> Details:-------------------------------------------------------
> Contact me: Tal.Galili at gmail.com |  972-52-7275845
> Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) |
> www.r-statistics.com (English)
>
----------------------------------------------------------------------------------------------
> 
> 	[[alternative HTML version deleted]]
> 
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