[Gretl-devel] Re: MPI and OpenMP (and openblas?)
On 16.01.2020 12:22, Sven Schreiber wrote:
Hi, here's a question about what is really affected by setting
the
number of threads used by OpenMP via an environment variable and/or via
the option to an MPI block (as explained in the gretl + MPI
documentation).
By setting "--omp-threads=1" in MPI block you implicit define "set
omp_num_threads 1" in 'gretltmp-mpi.inp' script which is ran by all
gretlmpi executables.
But the fact is that in many cases some routines runs in parallel via
OpenMP no matter what is the value of "omp_num_threads". I remember that
2-3 years ago Jack explained me that some algebra stuff lauch OpenMP
automagically.
Regards,
Marcin
--
Marcin Błażejowski