Patrick,
In the worst case scenario, requiring MPI_THREAD_MULTIPLE support can
disable some fast interconnect
and make your app fallback on IPoIB or similar. And in that case, Open MPI
might prefer a suboptimal
IP network which can impact the overall performances even more.
Which threading suppo
Le 28/02/2022 à 17:56, Patrick Begou via users a écrit :
Hi,
I meet a performance problem with OpenMPI on my cluster. In some
situation my parallel code is really slow (same binary running on a
different mesh).
To investigate, the fortran code code is built with profiling option
(mpifort -p
