On Sep 3, 2015, at 10:43 AM, Diego Avesani <diego.aves...@gmail.com> wrote: > > Dear Jeff, Dear all, > I normaly use "USE MPI" > > This is the answar fro intel HPC forum: > > If you are switching between intel and openmpi you must remember not to mix > environment. You might use modules to manage this.
I think the source of the confusion here might well be an overload of the word "modules". I think the word "module" in the phrase "You might use modules to manage this" is referring to *environment modules*, not *Fortran modules*. I.e.: http://modules.sourceforge.net/ Where you can do stuff like this: ----- # Use Open MPI $ module load openmpi $ mpicc my_program.c $ mpirun -np 4 a.out # Use __some_other_MPI__ $ module load othermpi $ mpicc my_program.c $ mpirun -np 4 a.out ----- Environment modules are typically used to set things like PATH, LD_LIBRARY_PATH, and MANPATH. I think the poster on the Intel HPC forum was probably referring to you using environment modules to switch your PATH / LD_LIBRARY_PATH / MANPATH between Open MPI and Intel MPI. > As the data types encodings differ, you must take care that all objects are > built against the same headers. Here, the poster is essentially saying that if you want to use Open MPI, you have to compile and mpirun with Open MPI. And if you want to use Open MPI, you have to (re)compile and mpirun with Intel MPI. In short: Open MPI and Intel MPI are not binary compatible, and their mpirun's are not compatible, either. (note that this is an Open MPI mailing list; we can't answer questions about Intel MPI here) My point with "use mpi" was that you should try replacing "include 'mpif.h'" with "use mpi" in your Fortran blocks. Open MPI's "use mpi" implementation will do a lot of compile-time type checking that "include 'mpif.h'" will not. Hence, it help determine if you're passing an incorrect parameter to an MPI subroutine, for example. -- Jeff Squyres jsquy...@cisco.com For corporate legal information go to: http://www.cisco.com/web/about/doing_business/legal/cri/
