%export MPI_USE_LIBELAN=0
8.9.10MPI_USE_LIBELAN_SUB
The use of Elan’s native collective operations may be extended to include communicators which are smaller than MPI_COMM_WORLD by setting the MPI_USE_LIBELAN_SUB environment variable to “TRUE”. By default, this functionality is disabled due to the fact that libelan memory resources are consumed and may eventually cause
%export MPI_USE_LIBELAN_USE=5
8.10MPICH Object Compatibility
The MPI standard specifies the function prototypes for the MPI functions, but does not specify the types of the MPI opaque objects like communicators or the values of the MPI constants. Hence an object file compiled using one vendor’s MPI will generally not function correctly if linked against another vendor’s MPI library.
There are some cases where such compatibility would be desirable. For instance a
To allow such compatibility,
1.2.5and cannot be used by an application which calls functions outside the scope of MPICH
An example of using a program with Vampir:
%$MPI_ROOT/bin/mpicc.mpich
%$MPI_ROOT/bin/mpirun.mpich
Here, the program communicator.c is being compiled with MPICH compatible interfaces and is being linked against Vampir’s libVT first from the command line option, followed by
In general, object files built with
communicator.c could be compiled under
% export MPI_ROOT=/opt/hpmpi%
$MPI_ROOT/bin/mpicc.mpich