Florian, My bad, I overlooked that.
Per the man page, the second parameter of MPI_Unpack() is the input buffer size in *bytes*. In your case, it should be packSize instead of vecSize. Makes sense ? FWIW, I never hesitate to run small tests with mpich (or its derivative). If both implementations fail, the odds are the problem is in the code and not in the library. Gilles Florian Lindner <mailingli...@xgm.de> wrote: >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 _______________________________________________ users mailing list users@lists.open-mpi.org https://lists.open-mpi.org/mailman/listinfo/users
