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

[Dirk Eddelbuettel]

On 18 July 2013 at 21:33, Dirk Eddelbuettel wrote:
| 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.

Sorry, I meant: "vignette for package parallel" -- that vignette is a good
read anyway.

And help(options) yields:

  Options set in package parallel:

     These will be set when package ‘parallel’ (or its namespace) is
     loaded if not already set.

     ‘mc.cores’: a integer giving the maximum allowed number of
          _additional_ R processes allowed to be run in parallel to the
          current R process.  Defaults to the setting of the
          environment variable ‘MC_CORES’ if set.  Most applications
          which use this assume a limit of ‘2’ if it is unset.

For OpenBLAS, see eg under 'Usage' at the bottom of 

   https://github.com/xianyi/OpenBLAS

It has been a while since I looked into this, but as I recall the option set
by R is respected one one possible option by OpenBLAS, which is why you end
up with 2 unless you set the number explicitly.

Dirk
 
| 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.
| 
| Dirk
| 
| -- 
| Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com

-- 
Dirk Eddelbuettel | edd at debian.org | http://dirk.eddelbuettel.com