Hi all, Can MPI_Session_Init be called with requesting MPI_THREAD_FUNNELED from two different threads? If so, does MPI return MPI_THREAD_FUNNELED or MPI_THREAD_SERIALIZED? Can I match this with MPI_Init_thread using MPI_THREAD_FUNNELED from a different thread? If we assume full isolation, that should work, right? Also, can I make two concurrent MPI calls from two different threads at the same time, assuming the MPI calls use MPI objects derived from two different sessions, both initialized with MPI_THREAD_SERIALIZED? Thanks, Martin -- Prof. Dr. Martin Schulz, Chair of Computer Architecture and Parallel Systems Department of Informatics, TU-Munich, Boltzmannstraße 3, D-85748 Garching Member of the Board of Directors at the Leibniz Supercomputing Centre (LRZ) Email: [email protected]