to my understanding OpenMP can be used when parallelizing within a
multicore node. It needs shared memory between the cores so
can't/shouldn't be used to parallelize across
different nodes. MPI does not need shared memory and can be used both
inside a multicore node and across nodes.
On 19/09/2016 12:01, Konrad Gruszka wrote:
I'm Writing to our community to clarify once and for all issues with
parallel pwscf execution.
By lecture of PWSCF manual, I know that there are several levels of
parallelization, including FFTW and more. At the same time, I'm quite
sure that most of beginner QE users do not have complicated clusters,
but are rather starting with decent multicore PC's.
There are two main parallel mechanisms (known to me) namely: MPI and
OpenMP. Because I'm using Ubuntu, there is free Hydra MPI software
(mpich) and also free OpenMP. From what I know (please correct me if
this is wrong) MPI software is used for parallelization within one
multicore PC and OpenMP is used to make parallelization between
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