Hi Gilles,
Am 14.02.2018 um 11:46 schrieb Gilles Gouaillardet: > Florian, > > You send position=0 MPI_PACKED instead of estimatedPackSize, so it is very > odd you see get_count = 12 > > Can you please double check that part ? https://gist.github.com/floli/310980790d5d76caac0b19a937e2a502 You mean in line 22: MPI_Isend(packSendBuf.data(), position, MPI_PACKED, 0, 0, MPI_COMM_WORLD, &req2); but position was incremented (to 12, see output below) by the preceding MPI_Pack call. > > Also, who returns MPI_ERR_TRUNCATE ? MPI_Recv ? MPI_Unpack ? Sorry, forgot to include that crucial part: % mpirun -n 1 ./a.out packSize = 12, estimatedPackSize = 12 position after pack = 12 packSize from get_count = 12 [asaru:30337] *** An error occurred in MPI_Unpack [asaru:30337] *** reported by process [4237492225,0] [asaru:30337] *** on communicator MPI_COMM_WORLD [asaru:30337] *** MPI_ERR_TRUNCATE: message truncated [asaru:30337] *** MPI_ERRORS_ARE_FATAL (processes in this communicator will now abort, [asaru:30337] *** and potentially your MPI job) Best Thanks, Florian > > > Cheers, > > Gilles > > Florian Lindner <mailingli...@xgm.de> wrote: >> Hello, >> >> I have this example code: >> >> #include <vector> >> #include <mpi.h> >> >> int main(int argc, char *argv[]) >> { >> MPI_Init(&argc, &argv); >> { >> MPI_Request req1, req2; >> std::vector<int> vec = {1, 2, 3}; >> int packSize = sizeof(int) * vec.size(); >> int position = 0; >> std::vector<char> packSendBuf(packSize); >> int vecSize = vec.size(); >> MPI_Pack(vec.data(), vec.size(), MPI_INT, packSendBuf.data(), packSize, >> &position, MPI_COMM_WORLD); >> >> int estimatedPackSize = 0; >> MPI_Pack_size(vec.size(), MPI_INT, MPI_COMM_WORLD, &estimatedPackSize); >> std::cout << "packSize = " << packSize << ", estimatedPackSize = " << >> estimatedPackSize << std::endl; >> >> MPI_Isend(&vecSize, 1, MPI_INT, 0, 0, MPI_COMM_WORLD, &req1); >> MPI_Isend(packSendBuf.data(), position, MPI_PACKED, 0, 0, MPI_COMM_WORLD, >> &req2); >> } >> { >> int vecSize, msgSize; >> int packSize = 0, position = 0; >> >> MPI_Recv(&vecSize, 1, MPI_INT, 0, MPI_ANY_TAG, MPI_COMM_WORLD, >> MPI_STATUS_IGNORE); >> >> MPI_Status status; >> MPI_Probe(0, MPI_ANY_TAG, MPI_COMM_WORLD, &status); >> MPI_Get_count(&status, MPI_PACKED, &packSize); >> char packBuffer[packSize]; >> std::cout << "packSize from get_count = " << packSize << std::endl; >> >> std::vector<int> vec(vecSize); >> MPI_Recv(packBuffer, packSize, MPI_PACKED, 0, MPI_ANY_TAG, >> MPI_COMM_WORLD, MPI_STATUS_IGNORE); >> MPI_Unpack(packBuffer, vecSize, &position, vec.data(), vecSize, MPI_INT, >> MPI_COMM_WORLD); >> } >> MPI_Finalize(); >> } >> >> >> Which gives an MPI_ERR_TRUNCATE even when running on 1 rank only. Background >> is that I want to send multiple differently >> sized objects, also with more complex types that to not map to MPI_*, for >> which I plan to use MPI_BYTES. I plan to pack >> them into one stream and unpack them one after one. >> >> I suspect I got somthig with the sizes wrong. The lines >> >> int estimatedPackSize = 0; >> MPI_Pack_size(vec.size(), MPI_INT, MPI_COMM_WORLD, &estimatedPackSize); >> std::cout << "packSize = " << packSize << ", estimatedPackSize = " << >> estimatedPackSize << std::endl; >> >> Return the same number, that is 12, the packSize from get_cont is also 12. >> >> Could you give a hint, what the is problem is here? >> >> OpenMPI 3.0.0 @ Arch or OpenMPI 1.1.0.2 @ Ubuntu 16.04 >> >> Thanks, >> Florian >> >> >> _______________________________________________ >> users mailing list >> users@lists.open-mpi.org >> https://lists.open-mpi.org/mailman/listinfo/users > _______________________________________________ > users mailing list > users@lists.open-mpi.org > https://lists.open-mpi.org/mailman/listinfo/users > _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users
