/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */ /* * (C) 2001 by Argonne National Laboratory. * See COPYRIGHT in top-level directory. */ #include "mpi.h" #include #include #include /* A 32^3 array. For other array sizes, change array_of_gsizes below. */ /* Uses collective I/O. Writes a 3D block-distributed array to a file corresponding to the global array in row-major (C) order, reads it back, and checks that the data read is correct. */ /* The file name is taken as a command-line argument. */ /* Note that the file access pattern is noncontiguous. */ void handle_error(int errcode, const char *str); void handle_error(int errcode, const char *str) { char msg[MPI_MAX_ERROR_STRING]; int resultlen; MPI_Error_string(errcode, msg, &resultlen); fprintf(stderr, "%s: %s\n", str, msg); MPI_Abort(MPI_COMM_WORLD, 1); } int main(int argc, char **argv) { MPI_Datatype newtype; int i, ndims, array_of_gsizes[3], array_of_distribs[3]; int order, nprocs, j, len; int array_of_dargs[3], array_of_psizes[3]; int *readbuf, *writebuf, mynod, *tmpbuf, array_size; MPI_Count bufcount; char *filename; int errs = 0, toterrs; MPI_File fh; MPI_Status status; MPI_Request request; MPI_Info info = MPI_INFO_NULL; int errcode; MPI_Init(&argc, &argv); MPI_Comm_rank(MPI_COMM_WORLD, &mynod); MPI_Comm_size(MPI_COMM_WORLD, &nprocs); /* process 0 takes the file name as a command-line argument and broadcasts it to other processes */ if (!mynod) { i = 1; while ((i < argc) && strcmp("-fname", *argv)) { i++; argv++; } if (i >= argc) { fprintf(stderr, "\n*# Usage: coll_test -fname filename\n\n"); MPI_Abort(MPI_COMM_WORLD, 1); } argv++; len = strlen(*argv); filename = (char *) malloc(len + 1); strcpy(filename, *argv); MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD); MPI_Bcast(filename, len + 1, MPI_CHAR, 0, MPI_COMM_WORLD); } else { MPI_Bcast(&len, 1, MPI_INT, 0, MPI_COMM_WORLD); filename = (char *) malloc(len + 1); MPI_Bcast(filename, len + 1, MPI_CHAR, 0, MPI_COMM_WORLD); } /* create the distributed array filetype */ ndims = 3; order = MPI_ORDER_C; array_of_gsizes[0] = 32; array_of_gsizes[1] = 32; array_of_gsizes[2] = 32; array_of_distribs[0] = MPI_DISTRIBUTE_BLOCK; array_of_distribs[1] = MPI_DISTRIBUTE_BLOCK; array_of_distribs[2] = MPI_DISTRIBUTE_BLOCK; array_of_dargs[0] = MPI_DISTRIBUTE_DFLT_DARG; array_of_dargs[1] = MPI_DISTRIBUTE_DFLT_DARG; array_of_dargs[2] = MPI_DISTRIBUTE_DFLT_DARG; for (i = 0; i < ndims; i++) array_of_psizes[i] = 0; MPI_Dims_create(nprocs, ndims, array_of_psizes); MPI_Type_create_darray(nprocs, mynod, ndims, array_of_gsizes, array_of_distribs, array_of_dargs, array_of_psizes, order, MPI_INT, &newtype); MPI_Type_commit(&newtype); /* initialize writebuf */ MPI_Type_size_x(newtype, &bufcount); bufcount = bufcount / sizeof(int); writebuf = (int *) malloc(bufcount * sizeof(int)); for (i = 0; i < bufcount; i++) writebuf[i] = 1; array_size = array_of_gsizes[0] * array_of_gsizes[1] * array_of_gsizes[2]; tmpbuf = (int *) calloc(array_size, sizeof(int)); MPI_Irecv(tmpbuf, 1, newtype, mynod, 10, MPI_COMM_WORLD, &request); MPI_Send(writebuf, bufcount, MPI_INT, mynod, 10, MPI_COMM_WORLD); MPI_Wait(&request, &status); j = 0; for (i = 0; i < array_size; i++) if (tmpbuf[i]) { writebuf[j] = i; j++; } free(tmpbuf); if (j != bufcount) { fprintf(stderr, "Error in initializing writebuf on process %d\n", mynod); MPI_Abort(MPI_COMM_WORLD, 1); } /* end of initialization */ /* write the array to the file */ errcode = MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_open"); errcode = MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_set_view"); errcode = MPI_File_write_all(fh, writebuf, bufcount, MPI_INT, &status); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_write_all"); errcode = MPI_File_close(&fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_close"); if (!mynod) { /* wkl suggests potential for false " No Errors" if both read * and write use the same file view */ /* solution: rank 0 reads entire file and checks write values */ errcode = MPI_File_open(MPI_COMM_SELF, filename, MPI_MODE_RDONLY, info, &fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_open"); readbuf = (int *) malloc(array_size * sizeof(int)); errcode = MPI_File_read(fh, readbuf, array_size, MPI_INT, &status); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_read"); errcode = MPI_File_close(&fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_close"); for (i = 0; i < array_size; i++) if (readbuf[i] != i) { errs++; fprintf(stderr, "Error: write integer %d but read %d\n", i, readbuf[i]); break; } free(readbuf); } MPI_Barrier(MPI_COMM_WORLD); /* now read it back */ readbuf = (int *) malloc(bufcount * sizeof(int)); errcode = MPI_File_open(MPI_COMM_WORLD, filename, MPI_MODE_CREATE | MPI_MODE_RDWR, info, &fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_open"); errcode = MPI_File_set_view(fh, 0, MPI_INT, newtype, "native", info); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_set_view"); errcode = MPI_File_read_all(fh, readbuf, bufcount, MPI_INT, &status); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_read_all"); errcode = MPI_File_close(&fh); if (errcode != MPI_SUCCESS) handle_error(errcode, "MPI_File_close"); /* check the data read */ for (i = 0; i < bufcount; i++) { if (readbuf[i] != writebuf[i]) { errs++; fprintf(stderr, "Process %d, readbuf %d, writebuf %d, i %d\n", mynod, readbuf[i], writebuf[i], i); } } MPI_Allreduce(&errs, &toterrs, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD); if (mynod == 0) { if (toterrs > 0) { fprintf(stderr, "Found %d errors\n", toterrs); } else { fprintf(stdout, " No Errors\n"); } } MPI_Type_free(&newtype); free(readbuf); free(writebuf); free(filename); MPI_Finalize(); return 0; }