Folks,
Jeff and i have been discussing the possibility of removing the
--enable-mpi-profile option from ompi.
(see https://github.com/open-mpi/ompi/pull/845 for the details)
Removing this option would simplify the building process, and make it
crystal clear that Fortran bindings call
the C PMPI_* bindings. From a tool point of view, that means a Fortran
MPI call is wrapped only once in Fortran.
Currently, a Fortran MPI call is wrapped twice, once in Fortran and once
in C.
We do not see any reason why someone would not want to build without the
PMPI_* bindings for a production build.
That being said, the --disable-mpi-profile option can be useful to
developers in order to build openmpi faster on a laptop running OSX. For
example, and on my MacBook (recent but low voltage cpu with two core and
two threads per core), the full build process (from autogen.pl to make
install) takes around 30 minutes, and not building the PMPI_* bindings
can save around 5 minutes.
/* when weak symbols are not available (e.g. ompi was configured with
--disable-weak-symbols or weak symbols are not available by the OS, OSX
for example), MPI bindings must be built twice:
- once to generate the MPI_* bindings
- an other time to generate the PMPI_* bindings */
any thoughts or objections to the removal of the --enable-mpi-profile
configure option ?
Cheers,
Gilles
