1 static char help[] = "Test that shared points on interface of partitions can be rebalanced.\n\n"; 2 static char FILENAME[] = "ex31.c"; 3 4 #include <petscdmplex.h> 5 #include <petscviewerhdf5.h> 6 #include <petscsf.h> 7 8 typedef struct { 9 PetscBool parallel; /* Use ParMetis or Metis */ 10 PetscBool useInitialGuess; /* Only active when in parallel, uses RefineKway of ParMetis */ 11 PetscInt entityDepth; /* depth of the entities to rebalance ( 0 => vertices) */ 12 } AppCtx; 13 14 static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options) 15 { 16 PetscFunctionBegin; 17 options->parallel = PETSC_FALSE; 18 options->useInitialGuess = PETSC_FALSE; 19 options->entityDepth = 0; 20 21 PetscOptionsBegin(comm, "", "Meshing Interpolation Test Options", "DMPLEX"); 22 PetscCall(PetscOptionsBoundedInt("-entity_depth", "Depth of the entities to rebalance (0 => vertices)", FILENAME, options->entityDepth, &options->entityDepth, NULL,0)); 23 PetscCall(PetscOptionsBool("-parallel", "Use ParMetis instead of Metis", FILENAME, options->parallel, &options->parallel, NULL)); 24 PetscCall(PetscOptionsBool("-use_initial_guess", "Use RefineKway function of ParMetis", FILENAME, options->useInitialGuess, &options->useInitialGuess, NULL)); 25 PetscOptionsEnd(); 26 PetscFunctionReturn(0); 27 } 28 29 static PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm) 30 { 31 PetscFunctionBegin; 32 PetscCall(DMCreate(comm, dm)); 33 PetscCall(DMSetType(*dm, DMPLEX)); 34 PetscCall(DMSetFromOptions(*dm)); 35 PetscCall(DMViewFromOptions(*dm, NULL, "-dm_view")); 36 PetscFunctionReturn(0); 37 } 38 39 int main(int argc, char **argv) 40 { 41 MPI_Comm comm; 42 DM dm, dmdist; 43 PetscPartitioner part; 44 AppCtx user; 45 IS is=NULL; 46 PetscSection s=NULL, gsection=NULL; 47 PetscMPIInt size; 48 PetscSF sf; 49 PetscInt pStart, pEnd, p, minBefore, maxBefore, minAfter, maxAfter, gSizeBefore, gSizeAfter; 50 PetscBool success; 51 52 PetscCall(PetscInitialize(&argc, &argv, NULL, help)); 53 comm = PETSC_COMM_WORLD; 54 PetscCallMPI(MPI_Comm_size(comm, &size)); 55 PetscCall(ProcessOptions(comm, &user)); 56 PetscCall(CreateMesh(comm, &user, &dm)); 57 58 /* partition dm using PETSCPARTITIONERPARMETIS */ 59 PetscCall(DMPlexGetPartitioner(dm, &part)); 60 PetscCall(PetscObjectSetOptionsPrefix((PetscObject)part,"p_")); 61 PetscCall(PetscPartitionerSetType(part, PETSCPARTITIONERPARMETIS)); 62 PetscCall(PetscPartitionerSetFromOptions(part)); 63 PetscCall(PetscSectionCreate(comm, &s)); 64 PetscCall(PetscPartitionerDMPlexPartition(part, dm, NULL, s, &is)); 65 66 PetscCall(DMPlexDistribute(dm, 0, NULL, &dmdist)); 67 if (dmdist) { 68 PetscCall(DMDestroy(&dm)); 69 dm = dmdist; 70 } 71 72 /* cleanup */ 73 PetscCall(PetscSectionDestroy(&s)); 74 PetscCall(ISDestroy(&is)); 75 76 /* We make a PetscSection with a DOF on every mesh entity of depth 77 * user.entityDepth, then make a global section and look at its storage size. 78 * We do the same thing after the rebalancing and then assert that the size 79 * remains the same. We also make sure that the balance has improved at least 80 * a little bit compared to the initial decomposition. */ 81 82 if (size>1) { 83 PetscCall(PetscSectionCreate(comm, &s)); 84 PetscCall(PetscSectionSetNumFields(s, 1)); 85 PetscCall(PetscSectionSetFieldComponents(s, 0, 1)); 86 PetscCall(DMPlexGetDepthStratum(dm, user.entityDepth, &pStart, &pEnd)); 87 PetscCall(PetscSectionSetChart(s, pStart, pEnd)); 88 for (p = pStart; p < pEnd; ++p) { 89 PetscCall(PetscSectionSetDof(s, p, 1)); 90 PetscCall(PetscSectionSetFieldDof(s, p, 0, 1)); 91 } 92 PetscCall(PetscSectionSetUp(s)); 93 PetscCall(DMGetPointSF(dm, &sf)); 94 PetscCall(PetscSectionCreateGlobalSection(s, sf, PETSC_FALSE, PETSC_FALSE, &gsection)); 95 PetscCall(PetscSectionGetStorageSize(gsection, &gSizeBefore)); 96 minBefore = gSizeBefore; 97 maxBefore = gSizeBefore; 98 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &gSizeBefore, 1, MPIU_INT, MPI_SUM, comm)); 99 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &minBefore, 1, MPIU_INT, MPI_MIN, comm)); 100 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &maxBefore, 1, MPIU_INT, MPI_MAX, comm)); 101 PetscCall(PetscSectionDestroy(&gsection)); 102 } 103 104 PetscCall(DMPlexRebalanceSharedPoints(dm, user.entityDepth, user.useInitialGuess, user.parallel, &success)); 105 106 if (size>1) { 107 PetscCall(PetscSectionCreateGlobalSection(s, sf, PETSC_FALSE, PETSC_FALSE, &gsection)); 108 PetscCall(PetscSectionGetStorageSize(gsection, &gSizeAfter)); 109 minAfter = gSizeAfter; 110 maxAfter = gSizeAfter; 111 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &gSizeAfter, 1, MPIU_INT, MPI_SUM, comm)); 112 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &minAfter, 1, MPIU_INT, MPI_MIN, comm)); 113 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, &maxAfter, 1, MPIU_INT, MPI_MAX, comm)); 114 PetscCheck(gSizeAfter == gSizeBefore,comm, PETSC_ERR_PLIB, "Global section has not the same size before and after."); 115 PetscCheck(minAfter >= minBefore && maxAfter <= maxBefore && (minAfter > minBefore || maxAfter < maxBefore),comm, PETSC_ERR_PLIB, "DMPlexRebalanceSharedPoints did not improve mesh point balance."); 116 PetscCall(PetscSectionDestroy(&gsection)); 117 PetscCall(PetscSectionDestroy(&s)); 118 } 119 120 PetscCall(DMDestroy(&dm)); 121 PetscCall(PetscFinalize()); 122 return 0; 123 } 124 125 /*TEST 126 127 testset: 128 args: -dm_plex_dim 3 -dm_plex_simplex 0 129 130 test: 131 # rebalance a mesh 132 suffix: 0 133 nsize: {{2 3 4}} 134 requires: parmetis 135 args: -dm_plex_box_faces {{2,3,4 5,4,3 7,11,5}} -entity_depth {{0 1}} -parallel {{FALSE TRUE}} -use_initial_guess FALSE 136 137 test: 138 # rebalance a mesh but use the initial guess (uses a random algorithm and gives different results on different machines, so just check that it runs). 139 suffix: 1 140 nsize: {{2 3 4}} 141 requires: parmetis 142 args: -dm_plex_box_faces {{2,3,4 5,4,3 7,11,5}} -entity_depth {{0 1}} -parallel TRUE -use_initial_guess TRUE 143 144 test: 145 # no-op in serial 146 suffix: 2 147 nsize: {{1}} 148 requires: parmetis 149 args: -dm_plex_box_faces 2,3,4 -entity_depth 0 -parallel FALSE -use_initial_guess FALSE 150 151 TEST*/ 152