Hello
My project has been using boost’s mpi interface for a number of years and have recently encountered a significant performance obstacle moving to openmpi 1.10.1. We are seeing a factor of 7-10x slowdown in the communication portion of our calculation. Our communication patterns are mostly governed by all-to-one reductions and some all-to-all reductions. Colleagues who call mpi directly have not seen this behavior.
I've seen similar slowdowns for ptp communication for a long time: http://lists.boost.org/boost-users/2015/02/83807.php including with other MPI implementations. If you can use git bisect on https://github.com/open-mpi/ompi to find in which commit your slowdown starts that might help a lot. Boost::mpi doesn't seem to be developed much nowadays even though there is git activity so unless you're transferring very complicated data types I'd consider skipping boost::mpi and using MPI directly. Ilja