1 // SPDX-FileCopyrightText: Copyright (c) 2017-2024, HONEE contributors. 2 // SPDX-License-Identifier: Apache-2.0 OR BSD-2-Clause 3 4 /// @file 5 /// Time-stepping functions for Navier-Stokes example using PETSc 6 7 #include <ceed.h> 8 #include <petscdmplex.h> 9 #include <petscts.h> 10 11 #include <navierstokes.h> 12 #include "../qfunctions/newtonian_state.h" 13 14 // @brief Insert Boundary values if it's a new time 15 PetscErrorCode UpdateBoundaryValues(User user, Vec Q_loc, PetscReal t) { 16 PetscFunctionBeginUser; 17 if (user->time_bc_set != t) { 18 PetscCall(DMPlexInsertBoundaryValues(user->dm, PETSC_TRUE, Q_loc, t, NULL, NULL, NULL)); 19 user->time_bc_set = t; 20 } 21 PetscFunctionReturn(PETSC_SUCCESS); 22 } 23 24 // RHS (Explicit time-stepper) function setup 25 // This is the RHS of the ODE, given as u_t = G(t,u) 26 // This function takes in a state vector Q and writes into G 27 PetscErrorCode RHS_NS(TS ts, PetscReal t, Vec Q, Vec G, void *user_data) { 28 User user = *(User *)user_data; 29 Ceed ceed = user->ceed; 30 PetscScalar dt; 31 Vec Q_loc = user->Q_loc; 32 PetscMemType q_mem_type; 33 34 PetscFunctionBeginUser; 35 // Update time dependent data 36 PetscCall(UpdateBoundaryValues(user, Q_loc, t)); 37 if (user->phys->solution_time_label) PetscCallCeed(ceed, CeedOperatorSetContextDouble(user->op_rhs_ctx->op, user->phys->solution_time_label, &t)); 38 PetscCall(TSGetTimeStep(ts, &dt)); 39 if (user->phys->timestep_size_label) PetscCallCeed(ceed, CeedOperatorSetContextDouble(user->op_rhs_ctx->op, user->phys->timestep_size_label, &dt)); 40 41 PetscCall(ApplyCeedOperatorGlobalToGlobal(Q, G, user->op_rhs_ctx)); 42 43 PetscCall(VecReadPetscToCeed(Q_loc, &q_mem_type, user->q_ceed)); 44 45 // Inverse of the mass matrix 46 PetscCall(KSPSolve(user->mass_ksp, G, G)); 47 48 PetscCall(VecReadCeedToPetsc(user->q_ceed, q_mem_type, Q_loc)); 49 PetscFunctionReturn(PETSC_SUCCESS); 50 } 51 52 // Surface forces function setup 53 static PetscErrorCode Surface_Forces_NS(DM dm, Vec G_loc, PetscInt num_walls, const PetscInt walls[], PetscScalar *reaction_force) { 54 DMLabel face_label; 55 const PetscScalar *g_array; 56 PetscInt dim = 3; 57 MPI_Comm comm = PetscObjectComm((PetscObject)dm); 58 PetscSection section; 59 60 PetscFunctionBeginUser; 61 PetscCall(DMGetLabel(dm, "Face Sets", &face_label)); 62 PetscCall(VecGetArrayRead(G_loc, &g_array)); 63 for (PetscInt w = 0; w < num_walls; w++) { 64 const PetscInt wall = walls[w], *points; 65 IS wall_is; 66 PetscInt num_points, num_comp = 0; 67 68 PetscCall(DMLabelGetStratumIS(face_label, wall, &wall_is)); 69 if (!wall_is) continue; // No wall points on this process, skip 70 71 PetscCall(DMGetLocalSection(dm, §ion)); 72 PetscCall(PetscSectionGetFieldComponents(section, 0, &num_comp)); 73 PetscCall(ISGetSize(wall_is, &num_points)); 74 PetscCall(ISGetIndices(wall_is, &points)); 75 for (PetscInt i = 0; i < num_points; i++) { 76 const PetscInt p = points[i]; 77 const StateConservative *r; 78 PetscInt dof; 79 80 PetscCall(DMPlexPointLocalRead(dm, p, g_array, &r)); 81 PetscCall(PetscSectionGetDof(section, p, &dof)); 82 for (PetscInt node = 0; node < dof / num_comp; node++) { 83 for (PetscInt j = 0; j < dim; j++) { 84 reaction_force[w * dim + j] -= r[node].momentum[j]; 85 } 86 } 87 } 88 PetscCall(ISRestoreIndices(wall_is, &points)); 89 PetscCall(ISDestroy(&wall_is)); 90 } 91 PetscCallMPI(MPI_Allreduce(MPI_IN_PLACE, reaction_force, dim * num_walls, MPIU_SCALAR, MPI_SUM, comm)); 92 PetscCall(VecRestoreArrayRead(G_loc, &g_array)); 93 PetscFunctionReturn(PETSC_SUCCESS); 94 } 95 96 // Implicit time-stepper function setup 97 PetscErrorCode IFunction_NS(TS ts, PetscReal t, Vec Q, Vec Q_dot, Vec G, void *user_data) { 98 User user = *(User *)user_data; 99 Ceed ceed = user->ceed; 100 PetscScalar dt; 101 Vec Q_loc = user->Q_loc, Q_dot_loc = user->Q_dot_loc, G_loc; 102 PetscMemType q_mem_type, q_dot_mem_type, g_mem_type; 103 104 PetscFunctionBeginUser; 105 // Get local vectors 106 PetscCall(DMGetNamedLocalVector(user->dm, "ResidualLocal", &G_loc)); 107 108 // Update time dependent data 109 PetscCall(UpdateBoundaryValues(user, Q_loc, t)); 110 if (user->phys->solution_time_label) PetscCallCeed(ceed, CeedOperatorSetContextDouble(user->op_ifunction, user->phys->solution_time_label, &t)); 111 PetscCall(TSGetTimeStep(ts, &dt)); 112 if (user->phys->timestep_size_label) PetscCallCeed(ceed, CeedOperatorSetContextDouble(user->op_ifunction, user->phys->timestep_size_label, &dt)); 113 114 // Global-to-local 115 PetscCall(DMGlobalToLocalBegin(user->dm, Q, INSERT_VALUES, Q_loc)); 116 PetscCall(DMGlobalToLocalBegin(user->dm, Q_dot, INSERT_VALUES, Q_dot_loc)); 117 PetscCall(DMGlobalToLocalEnd(user->dm, Q, INSERT_VALUES, Q_loc)); 118 if (user->app_ctx->divFdiffproj_method != DIV_DIFF_FLUX_PROJ_NONE) PetscCall(DivDiffFluxProjectionApply(user->diff_flux_proj, Q_loc)); 119 PetscCall(DMGlobalToLocalEnd(user->dm, Q_dot, INSERT_VALUES, Q_dot_loc)); 120 121 // Place PETSc vectors in CEED vectors 122 PetscCall(VecReadPetscToCeed(Q_loc, &q_mem_type, user->q_ceed)); 123 PetscCall(VecReadPetscToCeed(Q_dot_loc, &q_dot_mem_type, user->q_dot_ceed)); 124 PetscCall(VecPetscToCeed(G_loc, &g_mem_type, user->g_ceed)); 125 126 // Apply CEED operator 127 PetscCall(PetscLogEventBegin(FLUIDS_CeedOperatorApply, Q, G, 0, 0)); 128 PetscCall(PetscLogGpuTimeBegin()); 129 PetscCallCeed(user->ceed, CeedOperatorApply(user->op_ifunction, user->q_ceed, user->g_ceed, CEED_REQUEST_IMMEDIATE)); 130 PetscCall(PetscLogGpuTimeEnd()); 131 PetscCall(PetscLogEventEnd(FLUIDS_CeedOperatorApply, Q, G, 0, 0)); 132 133 // Restore vectors 134 PetscCall(VecReadCeedToPetsc(user->q_ceed, q_mem_type, Q_loc)); 135 PetscCall(VecReadCeedToPetsc(user->q_dot_ceed, q_dot_mem_type, Q_dot_loc)); 136 PetscCall(VecCeedToPetsc(user->g_ceed, g_mem_type, G_loc)); 137 138 if (user->app_ctx->sgs_model_type == SGS_MODEL_DATA_DRIVEN) { 139 PetscCall(SgsDDApplyIFunction(user, Q_loc, G_loc)); 140 } 141 142 // Local-to-Global 143 PetscCall(VecZeroEntries(G)); 144 PetscCall(DMLocalToGlobal(user->dm, G_loc, ADD_VALUES, G)); 145 146 // Restore vectors 147 PetscCall(DMRestoreNamedLocalVector(user->dm, "ResidualLocal", &G_loc)); 148 PetscFunctionReturn(PETSC_SUCCESS); 149 } 150 151 PetscErrorCode FormIJacobian_NS(TS ts, PetscReal t, Vec Q, Vec Q_dot, PetscReal shift, Mat J, Mat J_pre, void *user_data) { 152 User user = *(User *)user_data; 153 PetscBool J_is_matceed, J_is_mffd, J_pre_is_matceed, J_pre_is_mffd; 154 155 PetscFunctionBeginUser; 156 PetscCall(PetscObjectTypeCompare((PetscObject)J, MATMFFD, &J_is_mffd)); 157 PetscCall(PetscObjectTypeCompare((PetscObject)J, MATCEED, &J_is_matceed)); 158 PetscCall(PetscObjectTypeCompare((PetscObject)J_pre, MATMFFD, &J_pre_is_mffd)); 159 PetscCall(PetscObjectTypeCompare((PetscObject)J_pre, MATCEED, &J_pre_is_matceed)); 160 161 PetscCall(MatCeedSetContextReal(user->mat_ijacobian, "ijacobian time shift", shift)); 162 163 if (J_is_matceed || J_is_mffd) { 164 PetscCall(MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY)); 165 PetscCall(MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY)); 166 } else PetscCall(MatCeedAssembleCOO(user->mat_ijacobian, J)); 167 168 if (J_pre_is_matceed && J != J_pre) { 169 PetscCall(MatAssemblyBegin(J_pre, MAT_FINAL_ASSEMBLY)); 170 PetscCall(MatAssemblyEnd(J_pre, MAT_FINAL_ASSEMBLY)); 171 } else if (!J_pre_is_matceed && !J_pre_is_mffd && J != J_pre) { 172 PetscCall(MatCeedAssembleCOO(user->mat_ijacobian, J_pre)); 173 } 174 PetscFunctionReturn(PETSC_SUCCESS); 175 } 176 177 PetscErrorCode WriteOutput(User user, Vec Q, PetscInt step_no, PetscScalar time) { 178 Vec Q_loc; 179 char file_path[PETSC_MAX_PATH_LEN]; 180 PetscViewer viewer; 181 182 PetscFunctionBeginUser; 183 if (user->app_ctx->checkpoint_vtk) { 184 // Set up output 185 PetscCall(DMGetLocalVector(user->dm, &Q_loc)); 186 PetscCall(PetscObjectSetName((PetscObject)Q_loc, "StateVec")); 187 PetscCall(VecZeroEntries(Q_loc)); 188 PetscCall(DMGlobalToLocal(user->dm, Q, INSERT_VALUES, Q_loc)); 189 190 // Output 191 PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-%03" PetscInt_FMT ".vtu", user->app_ctx->output_dir, step_no)); 192 193 PetscCall(PetscViewerVTKOpen(PetscObjectComm((PetscObject)Q), file_path, FILE_MODE_WRITE, &viewer)); 194 PetscCall(VecView(Q_loc, viewer)); 195 PetscCall(PetscViewerDestroy(&viewer)); 196 if (user->dm_viz) { 197 Vec Q_refined, Q_refined_loc; 198 char file_path_refined[PETSC_MAX_PATH_LEN]; 199 PetscViewer viewer_refined; 200 201 PetscCall(DMGetGlobalVector(user->dm_viz, &Q_refined)); 202 PetscCall(DMGetLocalVector(user->dm_viz, &Q_refined_loc)); 203 PetscCall(PetscObjectSetName((PetscObject)Q_refined_loc, "Refined")); 204 205 PetscCall(MatInterpolate(user->interp_viz, Q, Q_refined)); 206 PetscCall(VecZeroEntries(Q_refined_loc)); 207 PetscCall(DMGlobalToLocal(user->dm_viz, Q_refined, INSERT_VALUES, Q_refined_loc)); 208 209 PetscCall( 210 PetscSNPrintf(file_path_refined, sizeof file_path_refined, "%s/nsrefined-%03" PetscInt_FMT ".vtu", user->app_ctx->output_dir, step_no)); 211 212 PetscCall(PetscViewerVTKOpen(PetscObjectComm((PetscObject)Q_refined), file_path_refined, FILE_MODE_WRITE, &viewer_refined)); 213 PetscCall(VecView(Q_refined_loc, viewer_refined)); 214 PetscCall(DMRestoreLocalVector(user->dm_viz, &Q_refined_loc)); 215 PetscCall(DMRestoreGlobalVector(user->dm_viz, &Q_refined)); 216 PetscCall(PetscViewerDestroy(&viewer_refined)); 217 } 218 PetscCall(DMRestoreLocalVector(user->dm, &Q_loc)); 219 } 220 221 // Save data in a binary file for continuation of simulations 222 if (user->app_ctx->add_stepnum2bin) { 223 PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-solution-%" PetscInt_FMT ".bin", user->app_ctx->output_dir, step_no)); 224 } else { 225 PetscCall(PetscSNPrintf(file_path, sizeof file_path, "%s/ns-solution.bin", user->app_ctx->output_dir)); 226 } 227 PetscCall(PetscViewerBinaryOpen(user->comm, file_path, FILE_MODE_WRITE, &viewer)); 228 229 time /= user->units->second; // Dimensionalize time back 230 PetscCall(HoneeWriteBinaryVec(viewer, Q, time, step_no)); 231 PetscCall(PetscViewerDestroy(&viewer)); 232 PetscFunctionReturn(PETSC_SUCCESS); 233 } 234 235 // CSV Monitor 236 PetscErrorCode TSMonitor_WallForce(TS ts, PetscInt step_no, PetscReal time, Vec Q, void *ctx) { 237 User user = ctx; 238 Vec G_loc; 239 PetscInt num_wall = user->app_ctx->wall_forces.num_wall, dim = 3; 240 const PetscInt *walls = user->app_ctx->wall_forces.walls; 241 PetscViewer viewer = user->app_ctx->wall_forces.viewer; 242 PetscViewerFormat format = user->app_ctx->wall_forces.viewer_format; 243 PetscScalar *reaction_force; 244 PetscBool is_ascii; 245 246 PetscFunctionBeginUser; 247 if (!viewer) PetscFunctionReturn(PETSC_SUCCESS); 248 PetscCall(DMGetNamedLocalVector(user->dm, "ResidualLocal", &G_loc)); 249 PetscCall(PetscCalloc1(num_wall * dim, &reaction_force)); 250 PetscCall(Surface_Forces_NS(user->dm, G_loc, num_wall, walls, reaction_force)); 251 PetscCall(DMRestoreNamedLocalVector(user->dm, "ResidualLocal", &G_loc)); 252 253 PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &is_ascii)); 254 255 if (is_ascii) { 256 if (format == PETSC_VIEWER_ASCII_CSV && !user->app_ctx->wall_forces.header_written) { 257 PetscCall(PetscViewerASCIIPrintf(viewer, "Step,Time,Wall,ForceX,ForceY,ForceZ\n")); 258 user->app_ctx->wall_forces.header_written = PETSC_TRUE; 259 } 260 for (PetscInt w = 0; w < num_wall; w++) { 261 PetscInt wall = walls[w]; 262 if (format == PETSC_VIEWER_ASCII_CSV) { 263 PetscCall(PetscViewerASCIIPrintf(viewer, "%" PetscInt_FMT ",%g,%" PetscInt_FMT ",%g,%g,%g\n", step_no, time, wall, 264 reaction_force[w * dim + 0], reaction_force[w * dim + 1], reaction_force[w * dim + 2])); 265 266 } else { 267 PetscCall(PetscViewerASCIIPrintf(viewer, "Wall %" PetscInt_FMT " Forces: Force_x = %12g, Force_y = %12g, Force_z = %12g\n", wall, 268 reaction_force[w * dim + 0], reaction_force[w * dim + 1], reaction_force[w * dim + 2])); 269 } 270 } 271 } 272 PetscCall(PetscFree(reaction_force)); 273 PetscFunctionReturn(PETSC_SUCCESS); 274 } 275 276 // User provided TS Monitor 277 PetscErrorCode TSMonitor_NS(TS ts, PetscInt step_no, PetscReal time, Vec Q, void *ctx) { 278 User user = ctx; 279 280 PetscFunctionBeginUser; 281 // Print every 'checkpoint_interval' steps 282 if (user->app_ctx->checkpoint_interval <= 0 || step_no % user->app_ctx->checkpoint_interval != 0 || 283 (user->app_ctx->cont_steps == step_no && step_no != 0)) { 284 PetscFunctionReturn(PETSC_SUCCESS); 285 } 286 287 PetscCall(WriteOutput(user, Q, step_no, time)); 288 PetscFunctionReturn(PETSC_SUCCESS); 289 } 290 291 // TS: Create, setup, and solve 292 PetscErrorCode TSSolve_NS(DM dm, User user, AppCtx app_ctx, Physics phys, ProblemData problem, Vec *Q, PetscScalar *f_time, TS *ts) { 293 MPI_Comm comm = user->comm; 294 TSAdapt adapt; 295 PetscScalar final_time; 296 297 PetscFunctionBeginUser; 298 PetscCall(TSCreate(comm, ts)); 299 PetscCall(TSSetDM(*ts, dm)); 300 PetscCall(TSSetApplicationContext(*ts, user)); 301 if (phys->implicit) { 302 PetscCall(TSSetType(*ts, TSBDF)); 303 if (user->op_ifunction) { 304 PetscCall(TSSetIFunction(*ts, NULL, IFunction_NS, &user)); 305 } else { // Implicit integrators can fall back to using an RHSFunction 306 PetscCall(TSSetRHSFunction(*ts, NULL, RHS_NS, &user)); 307 } 308 if (user->mat_ijacobian) { 309 PetscCall(DMTSSetIJacobian(dm, FormIJacobian_NS, &user)); 310 } 311 } else { 312 PetscCheck(user->op_rhs_ctx, comm, PETSC_ERR_ARG_NULL, "Problem does not provide RHSFunction"); 313 PetscCall(TSSetType(*ts, TSRK)); 314 PetscCall(TSRKSetType(*ts, TSRK5F)); 315 PetscCall(TSSetRHSFunction(*ts, NULL, RHS_NS, &user)); 316 } 317 PetscCall(TSSetMaxTime(*ts, 500. * user->units->second)); 318 PetscCall(TSSetExactFinalTime(*ts, TS_EXACTFINALTIME_STEPOVER)); 319 if (app_ctx->test_type == TESTTYPE_NONE) PetscCall(TSSetErrorIfStepFails(*ts, PETSC_FALSE)); 320 PetscCall(TSSetTimeStep(*ts, 1.e-2 * user->units->second)); 321 PetscCall(TSGetAdapt(*ts, &adapt)); 322 PetscCall(TSAdaptSetStepLimits(adapt, 1.e-12 * user->units->second, 1.e2 * user->units->second)); 323 PetscCall(TSSetFromOptions(*ts)); 324 if (user->mat_ijacobian) { 325 if (app_ctx->amat_type && !strcmp(app_ctx->amat_type, MATSHELL)) { 326 SNES snes; 327 KSP ksp; 328 Mat Pmat, Amat; 329 330 PetscCall(TSGetSNES(*ts, &snes)); 331 PetscCall(SNESGetKSP(snes, &ksp)); 332 PetscCall(CreateSolveOperatorsFromMatCeed(ksp, user->mat_ijacobian, PETSC_FALSE, &Amat, &Pmat)); 333 PetscCall(TSSetIJacobian(*ts, user->mat_ijacobian, Pmat, NULL, NULL)); 334 PetscCall(MatDestroy(&Amat)); 335 PetscCall(MatDestroy(&Pmat)); 336 } 337 } 338 user->time_bc_set = -1.0; // require all BCs be updated 339 if (app_ctx->cont_steps) { // continue from previous timestep data 340 PetscInt count; 341 PetscViewer viewer; 342 343 if (app_ctx->cont_time <= 0) { // Legacy files did not include step number and time 344 PetscCall(PetscViewerBinaryOpen(comm, app_ctx->cont_time_file, FILE_MODE_READ, &viewer)); 345 PetscCall(PetscViewerBinaryRead(viewer, &app_ctx->cont_time, 1, &count, PETSC_REAL)); 346 PetscCall(PetscViewerDestroy(&viewer)); 347 PetscCheck(app_ctx->cont_steps != -1, comm, PETSC_ERR_ARG_INCOMP, 348 "-continue step number not specified, but checkpoint file does not contain a step number (likely written by older code version)"); 349 } 350 PetscCall(TSSetTime(*ts, app_ctx->cont_time * user->units->second)); 351 PetscCall(TSSetStepNumber(*ts, app_ctx->cont_steps)); 352 } 353 if (app_ctx->test_type == TESTTYPE_NONE) { 354 PetscCall(TSMonitorSet(*ts, TSMonitor_NS, user, NULL)); 355 } 356 if (app_ctx->wall_forces.viewer) { 357 PetscCall(TSMonitorSet(*ts, TSMonitor_WallForce, user, NULL)); 358 } 359 if (app_ctx->turb_spanstats_enable) { 360 PetscCall(TSMonitorSet(*ts, TSMonitor_TurbulenceStatistics, user, NULL)); 361 CeedScalar previous_time = app_ctx->cont_time * user->units->second; 362 PetscCallCeed(user->ceed, 363 CeedOperatorSetContextDouble(user->spanstats.op_stats_collect_ctx->op, user->spanstats.previous_time_label, &previous_time)); 364 } 365 if (app_ctx->diff_filter_monitor) PetscCall(TSMonitorSet(*ts, TSMonitor_DifferentialFilter, user, NULL)); 366 367 if (app_ctx->sgs_train_enable) { 368 PetscCall(TSMonitorSet(*ts, TSMonitor_SGS_DD_Training, user, NULL)); 369 PetscCall(TSSetPostStep(*ts, TSPostStep_SGS_DD_Training)); 370 } 371 372 if (app_ctx->test_type == TESTTYPE_NONE) PetscCall(PrintRunInfo(user, user->phys, problem, *ts)); 373 // Solve 374 PetscReal start_time; 375 PetscInt start_step; 376 PetscCall(TSGetTime(*ts, &start_time)); 377 PetscCall(TSGetStepNumber(*ts, &start_step)); 378 379 PetscCall(PetscLogDefaultBegin()); // So we can use PetscLogStageGetPerfInfo without -log_view 380 PetscPreLoadBegin(PETSC_FALSE, "Fluids Solve"); 381 PetscCall(TSSetTime(*ts, start_time)); 382 PetscCall(TSSetStepNumber(*ts, start_step)); 383 if (PetscPreLoadingOn) { 384 // LCOV_EXCL_START 385 SNES snes; 386 Vec Q_preload; 387 PetscReal rtol; 388 PetscCall(VecDuplicate(*Q, &Q_preload)); 389 PetscCall(VecCopy(*Q, Q_preload)); 390 PetscCall(TSGetSNES(*ts, &snes)); 391 PetscCall(SNESGetTolerances(snes, NULL, &rtol, NULL, NULL, NULL)); 392 PetscCall(SNESSetTolerances(snes, PETSC_DEFAULT, .99, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT)); 393 PetscCall(TSSetSolution(*ts, Q_preload)); 394 PetscCall(TSStep(*ts)); 395 PetscCall(SNESSetTolerances(snes, PETSC_DEFAULT, rtol, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT)); 396 PetscCall(VecDestroy(&Q_preload)); 397 // LCOV_EXCL_STOP 398 } else { 399 PetscCall(PetscBarrier((PetscObject)*ts)); 400 PetscCall(TSSolve(*ts, *Q)); 401 } 402 PetscPreLoadEnd(); 403 404 PetscCall(TSGetSolveTime(*ts, &final_time)); 405 *f_time = final_time; 406 407 if (app_ctx->test_type == TESTTYPE_NONE) { 408 PetscInt step_no; 409 PetscCall(TSGetStepNumber(*ts, &step_no)); 410 if (user->app_ctx->checkpoint_interval > 0 || user->app_ctx->checkpoint_interval == -1) { 411 PetscCall(WriteOutput(user, *Q, step_no, final_time)); 412 } 413 414 PetscLogStage stage_id; 415 PetscEventPerfInfo stage_perf; 416 417 PetscCall(PetscLogStageGetId("Fluids Solve", &stage_id)); 418 PetscCall(PetscLogStageGetPerfInfo(stage_id, &stage_perf)); 419 PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Time taken for solution (sec): %g\n", stage_perf.time)); 420 } 421 PetscFunctionReturn(PETSC_SUCCESS); 422 } 423