Bill, please can you forward this to Yukiya Aoyama <aoyama_at_...>, the originator of this track. Thanks, Rolf ___________________________________ This is a proposal for MPI 2.1, Ballot 4. This is a follow up to: Description of the send and receive count arguments to MPI_Alltoallv in http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/index.h... with mail discussion in http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi-errata/discuss... Based on the questions for clarification, I propose not to include any further clarification into the standard. Reason: MPI-1, Sect. 4.8, MPI_ALLTOALLV, page 112, lines 37-40 clearly states: "The type signature associated with sendcount[j], sendtype at process i must be equal to the type signature associated with recvcount[i], recvtype at process j. This implies that the amount of data sent must be equal to the amount of data received, pairwise between every pair of processes. Distinct type maps between sender and receiver are still allowed." The same text is also used for MPI-2.0, Sect. 7.3.5 MPI_ALLTOALLW, page 165, lines 42-45. Okay? Best regards Rolf Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner_at_[hidden] High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530 University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832 Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner Nobelstr. 19, D-70550 Stuttgart, Germany . (Office: Allmandring 30)