1 static char help[] = "Compare parallel partitioning strategies using matrix graphs\n\n"; 2 3 #include <petscmat.h> 4 5 6 7 int main(int argc, char **args) 8 { 9 MatPartitioning part; 10 IS partis; 11 Mat A = NULL; 12 PetscInt max = -1; 13 PetscInt min = -1; 14 PetscReal balance = 0.0; 15 const PetscInt *ranges = NULL; 16 char filein[PETSC_MAX_PATH_LEN]; 17 MPI_Comm comm; 18 PetscMPIInt size; 19 PetscInt p; 20 PetscBool flg; 21 PetscErrorCode ierr; 22 23 /*load matrix*/ 24 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 25 comm = PETSC_COMM_WORLD; 26 ierr = MPI_Comm_size(comm, &size);CHKERRQ(ierr); 27 ierr = PetscOptionsGetString(NULL,NULL,"-fin",filein,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); 28 if (flg) { 29 PetscViewer view; 30 ierr = PetscViewerBinaryOpen(comm,filein,FILE_MODE_READ,&view);CHKERRQ(ierr); 31 ierr = MatCreate(comm,&A);CHKERRQ(ierr); 32 ierr = MatLoad(A,view);CHKERRQ(ierr); 33 ierr = PetscViewerDestroy(&view);CHKERRQ(ierr); 34 } 35 36 /*partition matrix*/ 37 ierr = MatPartitioningCreate(comm,&part);CHKERRQ(ierr); 38 ierr = MatPartitioningSetAdjacency(part, A);CHKERRQ(ierr); 39 ierr = MatPartitioningSetFromOptions(part);CHKERRQ(ierr); 40 ierr = MatPartitioningApply(part, &partis);CHKERRQ(ierr); 41 ierr = MatGetOwnershipRanges(A, &ranges);CHKERRQ(ierr); 42 ierr = MatGetSize(A, &min, NULL);CHKERRQ(ierr); 43 for (p = 0; p < size; ++p) { 44 const PetscInt partsize = ranges[p+1]-ranges[p]; 45 46 max = PetscMax(max, partsize); 47 min = PetscMin(min, partsize); 48 } 49 balance = ((PetscReal) max)/min; 50 ierr = PetscPrintf(comm, "ranges: ");CHKERRQ(ierr); 51 for (p = 0; p <= size; ++p) { 52 if (p > 0) {ierr = PetscPrintf(comm, ", ");CHKERRQ(ierr);} 53 ierr = PetscPrintf(comm, "%D", ranges[p]);CHKERRQ(ierr); 54 } 55 ierr = PetscPrintf(comm, "\n");CHKERRQ(ierr); 56 ierr = PetscPrintf(comm, "max:%.0lf min:%.0lf balance:%.11lf\n", (double) max,(double) min,(double) balance);CHKERRQ(ierr); 57 ierr = PetscObjectViewFromOptions((PetscObject)partis,NULL,"-partition_view");CHKERRQ(ierr); 58 ierr = MatPartitioningDestroy(&part);CHKERRQ(ierr); 59 ierr = ISDestroy(&partis);CHKERRQ(ierr); 60 ierr = MatDestroy(&A);CHKERRQ(ierr); 61 ierr = PetscFinalize(); 62 return ierr; 63 64 } 65