[Boost-users] [MPI] all_gather() missing functionality or bug ?

Hello list, I discovered that the all_gather function from boost.mp throws an exception, if the local sizes of the to be gathered vector are different: terminate called after throwing an instance of 'terminate called after throwing an instance of 'boost::exception_detail::clone_implboost::mpi::exception

' what(): MPI_Allgather: MPI_ERR_IN_STATUS: error code in status boost::exception_detail::clone_implboost::mpi::exception [thisch:14211] *** Process received signal ***

I used the following form of the all_gather function: all_gather(comm, myvec.data(), myvec.size(), totalvec) where myvec is a std::vector<double>. As already mentioned the size of myvec can be different on each processor. The documentation [0] says that all_gather supports most uses of the MPI_Allgatherv. Therefore I am not sure if my use of all_gather is unsupported or a just a bug. all_gather works as excpected if myvec.size() is the same on all processors. ATM I use the following workaround: { //temporary all_gather fix: use MPI_Allgatherv vector<int> recvcts(numprocs); vector<int> displs(numprocs); const int nrealcoeffs = N; const int initialcoeffsperrank = nrealcoeffs/numprocs; const int remainder = nrealcoeffs%numprocs; size_t displtmp = 0; for(size_t i=0; i < numprocs; i++){ recvcts[i] = initialcoeffsperrank; if(i < remainder) recvcts[i]++; displs[i] = displtmp; displtmp += recvcts[i]; } allgradient.resize(N); MPI_Allgatherv( myvec.data(), myvec.size(), MPI_DOUBLE, totalvec.data(), recvcts.data(), displs.data(), MPI_DOUBLE, comm); } Regards Thomas [0] http://www.boost.org/doc/libs/1_50_0/doc/html/mpi/tutorial.html#mpi.c_mappin...