Message-ID: <4B424855.8040101@braverock.com>
Date: 2010-01-04T19:58:13Z
From: Brian G. Peterson
Subject: mixing MP with MPI in R?
In-Reply-To: <6b93d1831001041123p2d668de9o4ce5ce442f9f2393@mail.gmail.com>
Mark Kimpel wrote:
> I recently ran into a problem that was easier to solve using mutilcore
> compared with Rmpi because I had a large matrix that I was performing
> calculations on and it copying it for each process ate up my 12GB of memory.
> I now have access to 2 Linux machine, each a core i7 with 12GB of memory,
> and wonder how I might speed things up even faster by using some sort of
> combination of multicore and Rmpi/snow.
>
> I'm a novice at this, so perhaps the answer is obvious, but is it possible
> to spawn to multiple machines with non-shared memory but within each machine
> used shared memory? If my novice understanding is correct, the former uses
> openMPI and the latter openMP.
>
> If this is possible, a self-contained example would be appreciated, even if
> the calculations are so trivial as to not make the parallelization
> worthwhile in the example case
>
>
See:
http://cran.r-project.org/web/packages/foreach/vignettes/nested.pdf
This should work fine with doMPI/doSnow and doMC
Regards,
- Brian
--
Brian G. Peterson
http://braverock.com/brian/
Ph: 773-459-4973
IM: bgpbraverock