xref: /libCEED/examples/petsc/bps.c (revision d7c2022436f3a8d683c91e7d2a1758d057ea5f30)
1 // Copyright (c) 2017, Lawrence Livermore National Security, LLC. Produced at
2 // the Lawrence Livermore National Laboratory. LLNL-CODE-734707. All Rights
3 // reserved. See files LICENSE and NOTICE for details.
4 //
5 // This file is part of CEED, a collection of benchmarks, miniapps, software
6 // libraries and APIs for efficient high-order finite element and spectral
7 // element discretizations for exascale applications. For more information and
8 // source code availability see http://github.com/ceed.
9 //
10 // The CEED research is supported by the Exascale Computing Project 17-SC-20-SC,
11 // a collaborative effort of two U.S. Department of Energy organizations (Office
12 // of Science and the National Nuclear Security Administration) responsible for
13 // the planning and preparation of a capable exascale ecosystem, including
14 // software, applications, hardware, advanced system engineering and early
15 // testbed platforms, in support of the nation's exascale computing imperative.
16 
17 //                        libCEED + PETSc Example: CEED BPs
18 //
19 // This example demonstrates a simple usage of libCEED with PETSc to solve the
20 // CEED BP benchmark problems, see http://ceed.exascaleproject.org/bps.
21 //
22 // The code uses higher level communication protocols in DMPlex.
23 //
24 // Build with:
25 //
26 //     make bps [PETSC_DIR=</path/to/petsc>] [CEED_DIR=</path/to/libceed>]
27 //
28 // Sample runs:
29 //
30 //     ./bps -problem bp1 -degree 3
31 //     ./bps -problem bp2 -ceed /cpu/self -degree 3
32 //     ./bps -problem bp3 -ceed /gpu/occa -degree 3
33 //     ./bps -problem bp4 -ceed /cpu/occa -degree 3
34 //     ./bps -problem bp5 -ceed /omp/occa -degree 3
35 //     ./bps -problem bp6 -ceed /ocl/occa -degree 3
36 //
37 //TESTARGS -ceed {ceed_resource} -test -problem bp5 -degree 3
38 
39 /// @file
40 /// CEED BPs example using PETSc with DMPlex
41 /// See bpsraw.c for a "raw" implementation using a structured grid.
42 const char help[] = "Solve CEED BPs using PETSc with DMPlex\n";
43 
44 #include <stdbool.h>
45 #include <string.h>
46 #include <petscksp.h>
47 #include <petscdmplex.h>
48 #include <ceed.h>
49 #include "setup.h"
50 
51 int main(int argc, char **argv) {
52   PetscInt ierr;
53   MPI_Comm comm;
54   char filename[PETSC_MAX_PATH_LEN],
55        ceedresource[PETSC_MAX_PATH_LEN] = "/cpu/self";
56   double my_rt_start, my_rt, rt_min, rt_max;
57   PetscInt degree = 3, qextra, lsize, gsize, dim = 3, melem[3] = {3, 3, 3},
58            ncompu = 1, xlsize, localnodes, lelem;
59   PetscScalar *r;
60   PetscBool test_mode, benchmark_mode, read_mesh, write_solution,
61             userlnodes = PETSC_FALSE;
62   PetscLogStage solvestage;
63   Vec X, Xloc, rhs, rhsloc;
64   Mat matO;
65   KSP ksp;
66   DM  dm;
67   UserO userO;
68   Ceed ceed;
69   CeedData ceeddata;
70   CeedQFunction qferror;
71   CeedOperator operror;
72   CeedVector rhsceed, target;
73   CeedMemType memtyperequested;
74   bpType bpchoice;
75 
76   // Check PETSc CUDA support
77   PetscBool petschavecuda, setmemtyperequest = PETSC_FALSE;
78   // *INDENT-OFF*
79   #ifdef PETSC_HAVE_CUDA
80   petschavecuda = PETSC_TRUE;
81   #else
82   petschavecuda = PETSC_FALSE;
83   #endif
84   // *INDENT-ON*
85 
86   ierr = PetscInitialize(&argc, &argv, NULL, help);
87   if (ierr) return ierr;
88   comm = PETSC_COMM_WORLD;
89 
90   // Read command line options
91   ierr = PetscOptionsBegin(comm, NULL, "CEED BPs in PETSc", NULL); CHKERRQ(ierr);
92   bpchoice = CEED_BP1;
93   ierr = PetscOptionsEnum("-problem",
94                           "CEED benchmark problem to solve", NULL,
95                           bpTypes, (PetscEnum)bpchoice, (PetscEnum *)&bpchoice,
96                           NULL); CHKERRQ(ierr);
97   ncompu = bpOptions[bpchoice].ncompu;
98   test_mode = PETSC_FALSE;
99   ierr = PetscOptionsBool("-test",
100                           "Testing mode (do not print unless error is large)",
101                           NULL, test_mode, &test_mode, NULL); CHKERRQ(ierr);
102   benchmark_mode = PETSC_FALSE;
103   ierr = PetscOptionsBool("-benchmark",
104                           "Benchmarking mode (prints benchmark statistics)",
105                           NULL, benchmark_mode, &benchmark_mode, NULL);
106   CHKERRQ(ierr);
107   write_solution = PETSC_FALSE;
108   ierr = PetscOptionsBool("-write_solution",
109                           "Write solution for visualization",
110                           NULL, write_solution, &write_solution, NULL);
111   CHKERRQ(ierr);
112   degree = test_mode ? 3 : 2;
113   ierr = PetscOptionsInt("-degree", "Polynomial degree of tensor product basis",
114                          NULL, degree, &degree, NULL); CHKERRQ(ierr);
115   qextra = bpOptions[bpchoice].qextra;
116   ierr = PetscOptionsInt("-qextra", "Number of extra quadrature points",
117                          NULL, qextra, &qextra, NULL); CHKERRQ(ierr);
118   ierr = PetscOptionsString("-ceed", "CEED resource specifier",
119                             NULL, ceedresource, ceedresource,
120                             sizeof(ceedresource), NULL); CHKERRQ(ierr);
121   read_mesh = PETSC_FALSE;
122   ierr = PetscOptionsString("-mesh", "Read mesh from file", NULL,
123                             filename, filename, sizeof(filename), &read_mesh);
124   CHKERRQ(ierr);
125   if (!read_mesh) {
126     PetscInt tmp = dim;
127     ierr = PetscOptionsIntArray("-cells", "Number of cells per dimension", NULL,
128                                 melem, &tmp, NULL); CHKERRQ(ierr);
129   }
130   memtyperequested = petschavecuda ? CEED_MEM_DEVICE : CEED_MEM_HOST;
131   ierr = PetscOptionsEnum("-memtype",
132                           "CEED MemType requested", NULL,
133                           memTypes, (PetscEnum)memtyperequested,
134                           (PetscEnum *)&memtyperequested, &setmemtyperequest);
135   CHKERRQ(ierr);
136   localnodes = 1000;
137   ierr = PetscOptionsInt("-local_nodes",
138                          "Target number of locally owned nodes per process",
139                          NULL, localnodes, &localnodes, &userlnodes);
140   CHKERRQ(ierr);
141 
142   ierr = PetscOptionsEnd(); CHKERRQ(ierr);
143 
144   // Setup DM
145   if (read_mesh) {
146     ierr = DMPlexCreateFromFile(PETSC_COMM_WORLD, filename, PETSC_TRUE, &dm);
147     CHKERRQ(ierr);
148   } else {
149     if (userlnodes) {
150       // Find a nicely composite number of elements no less than lnodes
151       for (lelem = PetscMax(1, localnodes / (degree*degree*degree)); ;
152            lelem++) {
153         Split3(lelem, melem, true);
154         if (Max3(melem) / Min3(melem) <= 2) break;
155       }
156     } else {
157       lelem = melem[0]*melem[1]*melem[2];
158     }
159     ierr = DMPlexCreateBoxMesh(PETSC_COMM_WORLD, dim, PETSC_FALSE, melem, NULL,
160                                NULL, NULL, PETSC_TRUE, &dm); CHKERRQ(ierr);
161   }
162 
163   {
164     DM dmDist = NULL;
165     PetscPartitioner part;
166 
167     ierr = DMPlexGetPartitioner(dm, &part); CHKERRQ(ierr);
168     ierr = PetscPartitionerSetFromOptions(part); CHKERRQ(ierr);
169     ierr = DMPlexDistribute(dm, 0, NULL, &dmDist); CHKERRQ(ierr);
170     if (dmDist) {
171       ierr = DMDestroy(&dm); CHKERRQ(ierr);
172       dm  = dmDist;
173     }
174   }
175 
176   // Set up libCEED
177   CeedInit(ceedresource, &ceed);
178   CeedMemType memtypebackend;
179   CeedGetPreferredMemType(ceed, &memtypebackend);
180 
181   // Check memtype compatibility
182   if (!setmemtyperequest)
183     memtyperequested = memtypebackend;
184   else if (!petschavecuda && memtyperequested == CEED_MEM_DEVICE)
185     SETERRQ1(PETSC_COMM_WORLD, PETSC_ERR_SUP_SYS,
186              "PETSc was not built with CUDA. "
187              "Requested MemType CEED_MEM_DEVICE is not supported.", NULL);
188 
189   // Create DM
190   ierr = SetupDMByDegree(dm, degree, ncompu, bpchoice);
191   CHKERRQ(ierr);
192 
193   // Create vectors
194   if (memtyperequested == CEED_MEM_DEVICE) {
195     ierr = DMSetVecType(dm, VECCUDA); CHKERRQ(ierr);
196   }
197   ierr = DMCreateGlobalVector(dm, &X); CHKERRQ(ierr);
198   ierr = VecGetLocalSize(X, &lsize); CHKERRQ(ierr);
199   ierr = VecGetSize(X, &gsize); CHKERRQ(ierr);
200   ierr = DMCreateLocalVector(dm, &Xloc); CHKERRQ(ierr);
201   ierr = VecGetSize(Xloc, &xlsize); CHKERRQ(ierr);
202   ierr = VecDuplicate(X, &rhs); CHKERRQ(ierr);
203 
204   // Operator
205   ierr = PetscMalloc1(1, &userO); CHKERRQ(ierr);
206   ierr = MatCreateShell(comm, lsize, lsize, gsize, gsize,
207                         userO, &matO); CHKERRQ(ierr);
208   ierr = MatShellSetOperation(matO, MATOP_MULT,
209                               (void(*)(void))MatMult_Ceed); CHKERRQ(ierr);
210   ierr = MatShellSetOperation(matO, MATOP_GET_DIAGONAL,
211                               (void(*)(void))MatGetDiag); CHKERRQ(ierr);
212   if (memtyperequested == CEED_MEM_DEVICE) {
213     ierr = MatShellSetVecType(matO, VECCUDA); CHKERRQ(ierr);
214   }
215 
216   // Print summary
217   if (!test_mode) {
218     PetscInt P = degree + 1, Q = P + qextra;
219 
220     const char *usedresource;
221     CeedGetResource(ceed, &usedresource);
222 
223     VecType vectype;
224     ierr = VecGetType(X, &vectype); CHKERRQ(ierr);
225 
226     ierr = PetscPrintf(comm,
227                        "\n-- CEED Benchmark Problem %d -- libCEED + PETSc --\n"
228                        "  PETSc:\n"
229                        "    PETSc Vec Type                     : %s\n"
230                        "  libCEED:\n"
231                        "    libCEED Backend                    : %s\n"
232                        "    libCEED Backend MemType            : %s\n"
233                        "    libCEED User Requested MemType     : %s\n"
234                        "  Mesh:\n"
235                        "    Number of 1D Basis Nodes (p)       : %d\n"
236                        "    Number of 1D Quadrature Points (q) : %d\n"
237                        "    Global nodes                       : %D\n"
238                        "    Owned nodes                        : %D\n"
239                        "    DoF per node                       : %D\n"
240                        "    Owned elements                     : %D\n",
241                        bpchoice+1, vectype, usedresource,
242                        CeedMemTypes[memtypebackend],
243                        (setmemtyperequest) ?
244                        CeedMemTypes[memtyperequested] : "none",
245                        P, Q, gsize/ncompu, lsize/ncompu, ncompu, lelem);
246     CHKERRQ(ierr);
247   }
248 
249   // Create RHS vector
250   ierr = VecDuplicate(Xloc, &rhsloc); CHKERRQ(ierr);
251   ierr = VecZeroEntries(rhsloc); CHKERRQ(ierr);
252   if (memtyperequested == CEED_MEM_HOST) {
253     ierr = VecGetArray(rhsloc, &r); CHKERRQ(ierr);
254   } else {
255     ierr = VecCUDAGetArray(rhsloc, &r); CHKERRQ(ierr);
256   }
257   CeedVectorCreate(ceed, xlsize, &rhsceed);
258   CeedVectorSetArray(rhsceed, memtyperequested, CEED_USE_POINTER, r);
259 
260   ierr = PetscMalloc1(1, &ceeddata); CHKERRQ(ierr);
261   ierr = SetupLibceedByDegree(dm, ceed, degree, dim, qextra,
262                               ncompu, gsize, xlsize, bpchoice, ceeddata,
263                               true, rhsceed, &target); CHKERRQ(ierr);
264 
265   // Gather RHS
266   CeedVectorSyncArray(rhsceed, memtyperequested);
267   if (memtyperequested == CEED_MEM_HOST) {
268     ierr = VecRestoreArray(rhsloc, &r); CHKERRQ(ierr);
269   } else {
270     ierr = VecCUDARestoreArray(rhsloc, &r); CHKERRQ(ierr);
271   }
272   ierr = VecZeroEntries(rhs); CHKERRQ(ierr);
273   ierr = DMLocalToGlobalBegin(dm, rhsloc, ADD_VALUES, rhs); CHKERRQ(ierr);
274   ierr = DMLocalToGlobalEnd(dm, rhsloc, ADD_VALUES, rhs); CHKERRQ(ierr);
275   CeedVectorDestroy(&rhsceed);
276 
277   // Create the error Q-function
278   CeedQFunctionCreateInterior(ceed, 1, bpOptions[bpchoice].error,
279                               bpOptions[bpchoice].errorfname, &qferror);
280   CeedQFunctionAddInput(qferror, "u", ncompu, CEED_EVAL_INTERP);
281   CeedQFunctionAddInput(qferror, "true_soln", ncompu, CEED_EVAL_NONE);
282   CeedQFunctionAddOutput(qferror, "error", ncompu, CEED_EVAL_NONE);
283 
284   // Create the error operator
285   CeedOperatorCreate(ceed, qferror, CEED_QFUNCTION_NONE, CEED_QFUNCTION_NONE,
286                      &operror);
287   CeedOperatorSetField(operror, "u", ceeddata->Erestrictu,
288                        ceeddata->basisu, CEED_VECTOR_ACTIVE);
289   CeedOperatorSetField(operror, "true_soln", ceeddata->Erestrictui,
290                        CEED_BASIS_COLLOCATED, target);
291   CeedOperatorSetField(operror, "error", ceeddata->Erestrictui,
292                        CEED_BASIS_COLLOCATED, CEED_VECTOR_ACTIVE);
293 
294   // Set up Mat
295   userO->comm = comm;
296   userO->dm = dm;
297   userO->Xloc = Xloc;
298   ierr = VecDuplicate(Xloc, &userO->Yloc); CHKERRQ(ierr);
299   userO->xceed = ceeddata->xceed;
300   userO->yceed = ceeddata->yceed;
301   userO->op = ceeddata->opapply;
302   userO->ceed = ceed;
303   userO->memtype = memtyperequested;
304   if (memtyperequested == CEED_MEM_HOST) {
305     userO->VecGetArray = VecGetArray;
306     userO->VecGetArrayRead = VecGetArrayRead;
307     userO->VecRestoreArray = VecRestoreArray;
308     userO->VecRestoreArrayRead = VecRestoreArrayRead;
309   } else {
310     userO->VecGetArray = VecCUDAGetArray;
311     userO->VecGetArrayRead = VecCUDAGetArrayRead;
312     userO->VecRestoreArray = VecCUDARestoreArray;
313     userO->VecRestoreArrayRead = VecCUDARestoreArrayRead;
314   }
315 
316   ierr = KSPCreate(comm, &ksp); CHKERRQ(ierr);
317   {
318     PC pc;
319     ierr = KSPGetPC(ksp, &pc); CHKERRQ(ierr);
320     if (bpchoice == CEED_BP1 || bpchoice == CEED_BP2) {
321       ierr = PCSetType(pc, PCJACOBI); CHKERRQ(ierr);
322       ierr = PCJacobiSetType(pc, PC_JACOBI_ROWSUM); CHKERRQ(ierr);
323     } else {
324       ierr = PCSetType(pc, PCNONE); CHKERRQ(ierr);
325     }
326     ierr = KSPSetType(ksp, KSPCG); CHKERRQ(ierr);
327     ierr = KSPSetNormType(ksp, KSP_NORM_NATURAL); CHKERRQ(ierr);
328     ierr = KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT,
329                             PETSC_DEFAULT); CHKERRQ(ierr);
330   }
331   ierr = KSPSetOperators(ksp, matO, matO); CHKERRQ(ierr);
332 
333   // First run, if benchmarking
334   if (benchmark_mode) {
335     ierr = KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 1);
336     CHKERRQ(ierr);
337     my_rt_start = MPI_Wtime();
338     ierr = KSPSolve(ksp, rhs, X); CHKERRQ(ierr);
339     my_rt = MPI_Wtime() - my_rt_start;
340     ierr = MPI_Allreduce(MPI_IN_PLACE, &my_rt, 1, MPI_DOUBLE, MPI_MIN, comm);
341     CHKERRQ(ierr);
342     // Set maxits based on first iteration timing
343     if (my_rt > 0.02) {
344       ierr = KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 5);
345       CHKERRQ(ierr);
346     } else {
347       ierr = KSPSetTolerances(ksp, 1e-10, PETSC_DEFAULT, PETSC_DEFAULT, 20);
348       CHKERRQ(ierr);
349     }
350   }
351   ierr = KSPSetFromOptions(ksp); CHKERRQ(ierr);
352 
353   // Timed solve
354   ierr = VecZeroEntries(X); CHKERRQ(ierr);
355   ierr = PetscBarrier((PetscObject)ksp); CHKERRQ(ierr);
356 
357   // -- Performance logging
358   ierr = PetscLogStageRegister("Solve Stage", &solvestage); CHKERRQ(ierr);
359   ierr = PetscLogStagePush(solvestage); CHKERRQ(ierr);
360 
361   // -- Solve
362   my_rt_start = MPI_Wtime();
363   ierr = KSPSolve(ksp, rhs, X); CHKERRQ(ierr);
364   my_rt = MPI_Wtime() - my_rt_start;
365 
366   // -- Performance logging
367   ierr = PetscLogStagePop();
368 
369   // Output results
370   {
371     KSPType ksptype;
372     KSPConvergedReason reason;
373     PetscReal rnorm;
374     PetscInt its;
375     ierr = KSPGetType(ksp, &ksptype); CHKERRQ(ierr);
376     ierr = KSPGetConvergedReason(ksp, &reason); CHKERRQ(ierr);
377     ierr = KSPGetIterationNumber(ksp, &its); CHKERRQ(ierr);
378     ierr = KSPGetResidualNorm(ksp, &rnorm); CHKERRQ(ierr);
379     if (!test_mode || reason < 0 || rnorm > 1e-8) {
380       ierr = PetscPrintf(comm,
381                          "  KSP:\n"
382                          "    KSP Type                           : %s\n"
383                          "    KSP Convergence                    : %s\n"
384                          "    Total KSP Iterations               : %D\n"
385                          "    Final rnorm                        : %e\n",
386                          ksptype, KSPConvergedReasons[reason], its,
387                          (double)rnorm); CHKERRQ(ierr);
388     }
389     if (!test_mode) {
390       ierr = PetscPrintf(comm,"  Performance:\n"); CHKERRQ(ierr);
391     }
392     {
393       PetscReal maxerror;
394       ierr = ComputeErrorMax(userO, operror, X, target, &maxerror);
395       CHKERRQ(ierr);
396       PetscReal tol = 5e-2;
397       if (!test_mode || maxerror > tol) {
398         ierr = MPI_Allreduce(&my_rt, &rt_min, 1, MPI_DOUBLE, MPI_MIN, comm);
399         CHKERRQ(ierr);
400         ierr = MPI_Allreduce(&my_rt, &rt_max, 1, MPI_DOUBLE, MPI_MAX, comm);
401         CHKERRQ(ierr);
402         ierr = PetscPrintf(comm,
403                            "    Pointwise Error (max)              : %e\n"
404                            "    CG Solve Time                      : %g (%g) sec\n",
405                            (double)maxerror, rt_max, rt_min); CHKERRQ(ierr);
406       }
407     }
408     if (benchmark_mode && (!test_mode)) {
409       ierr = PetscPrintf(comm,
410                          "    DoFs/Sec in CG                     : %g (%g) million\n",
411                          1e-6*gsize*its/rt_max,
412                          1e-6*gsize*its/rt_min); CHKERRQ(ierr);
413     }
414   }
415 
416   if (write_solution) {
417     PetscViewer vtkviewersoln;
418 
419     ierr = PetscViewerCreate(comm, &vtkviewersoln); CHKERRQ(ierr);
420     ierr = PetscViewerSetType(vtkviewersoln, PETSCVIEWERVTK); CHKERRQ(ierr);
421     ierr = PetscViewerFileSetName(vtkviewersoln, "solution.vtk"); CHKERRQ(ierr);
422     ierr = VecView(X, vtkviewersoln); CHKERRQ(ierr);
423     ierr = PetscViewerDestroy(&vtkviewersoln); CHKERRQ(ierr);
424   }
425 
426   // Cleanup
427   ierr = VecDestroy(&X); CHKERRQ(ierr);
428   ierr = VecDestroy(&Xloc); CHKERRQ(ierr);
429   ierr = VecDestroy(&userO->Yloc); CHKERRQ(ierr);
430   ierr = MatDestroy(&matO); CHKERRQ(ierr);
431   ierr = PetscFree(userO); CHKERRQ(ierr);
432   ierr = CeedDataDestroy(0, ceeddata); CHKERRQ(ierr);
433   ierr = DMDestroy(&dm); CHKERRQ(ierr);
434 
435   ierr = VecDestroy(&rhs); CHKERRQ(ierr);
436   ierr = VecDestroy(&rhsloc); CHKERRQ(ierr);
437   ierr = KSPDestroy(&ksp); CHKERRQ(ierr);
438   CeedVectorDestroy(&target);
439   CeedQFunctionDestroy(&qferror);
440   CeedOperatorDestroy(&operror);
441   CeedDestroy(&ceed);
442   return PetscFinalize();
443 }
444