How do I compile MPI code on HPCVL?

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The compilation of MPI programs requires a few compiler options to direct the compiler to the location of header files and libraries. Since these switches are always the same, they have been collected in a macro to avoid unnecessary typing. The macro is has an mp or mpi prefix before the normal compiler name, for ClusterTools 6 or ClusterTools 7 and higher, repsectively. The commands are mpf90 or mpi90 for Fortran 90 compiler, and mpcc, mpicc, mpCC, and mpiCC for the C and C++ compilers, respectively. For instance, if a serial C program is compiled by

cc -xO3 -c test.c

the corresponding parallel (MPI) program is compiled by

mpcc -xO3 -c test_mpi.c [ClusterTools 6]
mpicc -xO3 -c test_mpi.c [ClusterTools 8.1]

In the linking stage, the specification of the MPI libraries is required for ClusterTools 6. This is done via the -lmpi option. For ClusterTools 7 and higher this inclusion is automatic. For example, the above MPI program should be linked with something like this:

mpcc -o test_mpi.exe test_mpi.o -lmpi [ClusterTools 6] 
mpicc -o test_mpi.exe test_mpi.o [ClusterTools 8.1]

Compiling and linking may also be combined.