[R] R performance: different CPUs

[Jasjeet Singh Sekhon]

Hi,

64bit CPUs, such as opterons, help significantly with large databases
or if you are running multiple processes.  But there is a speed
penalty if you are not.

Some packages can make use of multiple processors, such as my rgenoud
(genetic optimization using derivatives) and Matching packages, but
most do not.  For these packages the speed up is significant.  There
are also multithreaded BLAS which can be used reliably under LINUX,
but the speed benefit is usually small.

You may want to check out some benchmarks at:

http://sekhon.berkeley.edu/macosx/ (linux does very well).

Cheers,
JS.

=======================================
Jasjeet S. Sekhon                     
                                      
Associate Professor             
Survey Research Center          
UC Berkeley                     

http://sekhon.berkeley.edu/
V: 510-642-9974  F: 617-507-5524
=======================================







Toby Muhlhofer writes:
 > Hello!
 > 
 > I need to purchase a new box, which I would like to optimize for good R 
 > performance.
 > 
 > For the record, I will run Fedora Core 5 as and OS, and I wanted to know 
 > if anyone has experience with how the following affects R performance:
 > 
 > - Is there a big advantage to having a 64-bit CPU over having a 32-bit?
 > 
 > - Does an Opteron offer any advantages over an Athlon, and if yes, does 
 > it justify an investment of about US $75 more for equivalent listed speeds?
 > 
 > - Have people successfully multithreaded R computations, such as to 
 > justify a dual-core CPU? I understand R itself does not multithread, but 
 >   of course it should be possible to write code that paralellizes 
 > computations and I wanted to know if anyone has experience doing so and 
 > gained large speed advantages by it.
 > 
 > Thanks,
 > 	Toby Muhlhfoer
 > 
 >