Actual source code: asm.c
1: /*
2: This file defines an additive Schwarz preconditioner for any Mat implementation.
4: Note that each processor may have any number of subdomains. But in order to
5: deal easily with the VecScatter(), we treat each processor as if it has the
6: same number of subdomains.
8: n - total number of true subdomains on all processors
9: n_local_true - actual number of subdomains on this processor
10: n_local = maximum over all processors of n_local_true
11: */
13: #include <petsc/private/pcasmimpl.h>
14: #include <petsc/private/matimpl.h>
16: static PetscErrorCode PCView_ASM(PC pc, PetscViewer viewer)
17: {
18: PC_ASM *osm = (PC_ASM *)pc->data;
19: PetscMPIInt rank;
20: PetscInt i, bsz;
21: PetscBool isascii, isstring;
22: PetscViewer sviewer;
23: PetscViewerFormat format;
24: const char *prefix;
26: PetscFunctionBegin;
27: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &isascii));
28: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERSTRING, &isstring));
29: if (isascii) {
30: char overlaps[256] = "user-defined overlap", blocks[256] = "total subdomain blocks not yet set";
31: if (osm->overlap >= 0) PetscCall(PetscSNPrintf(overlaps, sizeof(overlaps), "amount of overlap = %" PetscInt_FMT, osm->overlap));
32: if (osm->n > 0) PetscCall(PetscSNPrintf(blocks, sizeof(blocks), "total subdomain blocks = %" PetscInt_FMT, osm->n));
33: PetscCall(PetscViewerASCIIPrintf(viewer, " %s, %s\n", blocks, overlaps));
34: PetscCall(PetscViewerASCIIPrintf(viewer, " restriction/interpolation type - %s\n", PCASMTypes[osm->type]));
35: if (osm->dm_subdomains) PetscCall(PetscViewerASCIIPrintf(viewer, " Additive Schwarz: using DM to define subdomains\n"));
36: if (osm->loctype != PC_COMPOSITE_ADDITIVE) PetscCall(PetscViewerASCIIPrintf(viewer, " Additive Schwarz: local solve composition type - %s\n", PCCompositeTypes[osm->loctype]));
37: PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc), &rank));
38: PetscCall(PetscViewerGetFormat(viewer, &format));
39: if (format != PETSC_VIEWER_ASCII_INFO_DETAIL) {
40: if (osm->ksp) {
41: PetscCall(PetscViewerASCIIPrintf(viewer, " Local solver information for first block is in the following KSP and PC objects on rank 0:\n"));
42: PetscCall(PCGetOptionsPrefix(pc, &prefix));
43: PetscCall(PetscViewerASCIIPrintf(viewer, " Use -%sksp_view ::ascii_info_detail to display information for all blocks\n", prefix ? prefix : ""));
44: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
45: if (rank == 0) {
46: PetscCall(PetscViewerASCIIPushTab(sviewer));
47: PetscCall(KSPView(osm->ksp[0], sviewer));
48: PetscCall(PetscViewerASCIIPopTab(sviewer));
49: }
50: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
51: }
52: } else {
53: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
54: PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, " [%d] number of local blocks = %" PetscInt_FMT "\n", rank, osm->n_local_true));
55: PetscCall(PetscViewerFlush(viewer));
56: PetscCall(PetscViewerASCIIPrintf(viewer, " Local solver information for each block is in the following KSP and PC objects:\n"));
57: PetscCall(PetscViewerASCIIPushTab(viewer));
58: PetscCall(PetscViewerASCIIPrintf(viewer, "- - - - - - - - - - - - - - - - - -\n"));
59: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
60: for (i = 0; i < osm->n_local_true; i++) {
61: PetscCall(ISGetLocalSize(osm->is[i], &bsz));
62: PetscCall(PetscViewerASCIIPrintf(sviewer, "[%d] local block number %" PetscInt_FMT ", size = %" PetscInt_FMT "\n", rank, i, bsz));
63: PetscCall(KSPView(osm->ksp[i], sviewer));
64: PetscCall(PetscViewerASCIIPrintf(sviewer, "- - - - - - - - - - - - - - - - - -\n"));
65: }
66: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
67: PetscCall(PetscViewerASCIIPopTab(viewer));
68: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
69: }
70: } else if (isstring) {
71: PetscCall(PetscViewerStringSPrintf(viewer, " blocks=%" PetscInt_FMT ", overlap=%" PetscInt_FMT ", type=%s", osm->n, osm->overlap, PCASMTypes[osm->type]));
72: PetscCall(PetscViewerGetSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
73: if (osm->ksp) PetscCall(KSPView(osm->ksp[0], sviewer));
74: PetscCall(PetscViewerRestoreSubViewer(viewer, PETSC_COMM_SELF, &sviewer));
75: }
76: PetscFunctionReturn(PETSC_SUCCESS);
77: }
79: static PetscErrorCode PCASMPrintSubdomains(PC pc)
80: {
81: PC_ASM *osm = (PC_ASM *)pc->data;
82: const char *prefix;
83: char fname[PETSC_MAX_PATH_LEN + 1];
84: PetscViewer viewer, sviewer;
85: char *s;
86: PetscInt i, j, nidx;
87: const PetscInt *idx;
88: PetscMPIInt rank, size;
90: PetscFunctionBegin;
91: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)pc), &size));
92: PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc), &rank));
93: PetscCall(PCGetOptionsPrefix(pc, &prefix));
94: PetscCall(PetscOptionsGetString(NULL, prefix, "-pc_asm_print_subdomains", fname, sizeof(fname), NULL));
95: if (fname[0] == 0) PetscCall(PetscStrncpy(fname, "stdout", sizeof(fname)));
96: PetscCall(PetscViewerASCIIOpen(PetscObjectComm((PetscObject)pc), fname, &viewer));
97: for (i = 0; i < osm->n_local; i++) {
98: if (i < osm->n_local_true) {
99: PetscCall(ISGetLocalSize(osm->is[i], &nidx));
100: PetscCall(ISGetIndices(osm->is[i], &idx));
101: /* Print to a string viewer; no more than 15 characters per index plus 512 char for the header.*/
102: #define len 16 * (nidx + 1) + 512
103: PetscCall(PetscMalloc1(len, &s));
104: PetscCall(PetscViewerStringOpen(PETSC_COMM_SELF, s, len, &sviewer));
105: #undef len
106: PetscCall(PetscViewerStringSPrintf(sviewer, "[%d:%d] Subdomain %" PetscInt_FMT " with overlap:\n", rank, size, i));
107: for (j = 0; j < nidx; j++) PetscCall(PetscViewerStringSPrintf(sviewer, "%" PetscInt_FMT " ", idx[j]));
108: PetscCall(ISRestoreIndices(osm->is[i], &idx));
109: PetscCall(PetscViewerStringSPrintf(sviewer, "\n"));
110: PetscCall(PetscViewerDestroy(&sviewer));
111: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
112: PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "%s", s));
113: PetscCall(PetscViewerFlush(viewer));
114: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
115: PetscCall(PetscFree(s));
116: if (osm->is_local) {
117: /* Print to a string viewer; no more than 15 characters per index plus 512 char for the header.*/
118: #define len 16 * (nidx + 1) + 512
119: PetscCall(PetscMalloc1(len, &s));
120: PetscCall(PetscViewerStringOpen(PETSC_COMM_SELF, s, len, &sviewer));
121: #undef len
122: PetscCall(PetscViewerStringSPrintf(sviewer, "[%d:%d] Subdomain %" PetscInt_FMT " without overlap:\n", rank, size, i));
123: PetscCall(ISGetLocalSize(osm->is_local[i], &nidx));
124: PetscCall(ISGetIndices(osm->is_local[i], &idx));
125: for (j = 0; j < nidx; j++) PetscCall(PetscViewerStringSPrintf(sviewer, "%" PetscInt_FMT " ", idx[j]));
126: PetscCall(ISRestoreIndices(osm->is_local[i], &idx));
127: PetscCall(PetscViewerStringSPrintf(sviewer, "\n"));
128: PetscCall(PetscViewerDestroy(&sviewer));
129: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
130: PetscCall(PetscViewerASCIISynchronizedPrintf(viewer, "%s", s));
131: PetscCall(PetscViewerFlush(viewer));
132: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
133: PetscCall(PetscFree(s));
134: }
135: } else {
136: /* Participate in collective viewer calls. */
137: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
138: PetscCall(PetscViewerFlush(viewer));
139: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
140: /* Assume either all ranks have is_local or none do. */
141: if (osm->is_local) {
142: PetscCall(PetscViewerASCIIPushSynchronized(viewer));
143: PetscCall(PetscViewerFlush(viewer));
144: PetscCall(PetscViewerASCIIPopSynchronized(viewer));
145: }
146: }
147: }
148: PetscCall(PetscViewerFlush(viewer));
149: PetscCall(PetscViewerDestroy(&viewer));
150: PetscFunctionReturn(PETSC_SUCCESS);
151: }
153: static PetscErrorCode PCSetUp_ASM(PC pc)
154: {
155: PC_ASM *osm = (PC_ASM *)pc->data;
156: PetscBool flg;
157: PetscInt i, m, m_local;
158: MatReuse scall = MAT_REUSE_MATRIX;
159: IS isl;
160: KSP ksp;
161: PC subpc;
162: const char *prefix, *pprefix;
163: Vec vec;
164: DM *domain_dm = NULL;
165: MatNullSpace *nullsp = NULL;
167: PetscFunctionBegin;
168: if (!pc->setupcalled) {
169: PetscInt m;
171: /* Note: if subdomains have been set either via PCASMSetTotalSubdomains() or via PCASMSetLocalSubdomains(), osm->n_local_true will not be PETSC_DECIDE */
172: if (osm->n_local_true == PETSC_DECIDE) {
173: /* no subdomains given */
174: /* try pc->dm first, if allowed */
175: if (osm->dm_subdomains && pc->dm) {
176: PetscInt num_domains;
177: char **domain_names;
178: IS *inner_domain_is, *outer_domain_is;
179: PetscCall(DMCreateDomainDecomposition(pc->dm, &num_domains, &domain_names, &inner_domain_is, &outer_domain_is, &domain_dm));
180: osm->overlap = -1; /* We do not want to increase the overlap of the IS.
181: A future improvement of this code might allow one to use
182: DM-defined subdomains and also increase the overlap,
183: but that is not currently supported */
184: if (num_domains) PetscCall(PCASMSetLocalSubdomains(pc, num_domains, outer_domain_is, inner_domain_is));
185: for (PetscInt d = 0; d < num_domains; ++d) {
186: if (domain_names) PetscCall(PetscFree(domain_names[d]));
187: if (inner_domain_is) PetscCall(ISDestroy(&inner_domain_is[d]));
188: if (outer_domain_is) PetscCall(ISDestroy(&outer_domain_is[d]));
189: }
190: PetscCall(PetscFree(domain_names));
191: PetscCall(PetscFree(inner_domain_is));
192: PetscCall(PetscFree(outer_domain_is));
193: }
194: if (osm->n_local_true == PETSC_DECIDE) {
195: /* still no subdomains; use one subdomain per processor */
196: osm->n_local_true = 1;
197: }
198: }
199: { /* determine the global and max number of subdomains */
200: struct {
201: PetscInt max, sum;
202: } inwork, outwork;
203: PetscMPIInt size;
205: inwork.max = osm->n_local_true;
206: inwork.sum = osm->n_local_true;
207: PetscCallMPI(MPIU_Allreduce(&inwork, &outwork, 1, MPIU_2INT, MPIU_MAXSUM_OP, PetscObjectComm((PetscObject)pc)));
208: osm->n_local = outwork.max;
209: osm->n = outwork.sum;
211: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)pc), &size));
212: if (outwork.max == 1 && outwork.sum == size) {
213: /* osm->n_local_true = 1 on all processes, set this option may enable use of optimized MatCreateSubMatrices() implementation */
214: PetscCall(MatSetOption(pc->pmat, MAT_SUBMAT_SINGLEIS, PETSC_TRUE));
215: }
216: }
217: if (!osm->is) { /* create the index sets */
218: PetscCall(PCASMCreateSubdomains(pc->pmat, osm->n_local_true, &osm->is));
219: }
220: if (osm->n_local_true > 1 && !osm->is_local) {
221: PetscCall(PetscMalloc1(osm->n_local_true, &osm->is_local));
222: for (i = 0; i < osm->n_local_true; i++) {
223: if (osm->overlap > 0) { /* With positive overlap, osm->is[i] will be modified */
224: PetscCall(ISDuplicate(osm->is[i], &osm->is_local[i]));
225: PetscCall(ISCopy(osm->is[i], osm->is_local[i]));
226: } else {
227: PetscCall(PetscObjectReference((PetscObject)osm->is[i]));
228: osm->is_local[i] = osm->is[i];
229: }
230: }
231: }
232: PetscCall(PCGetOptionsPrefix(pc, &prefix));
233: if (osm->overlap > 0) {
234: /* Extend the "overlapping" regions by a number of steps */
235: PetscCall(MatIncreaseOverlap(pc->pmat, osm->n_local_true, osm->is, osm->overlap));
236: }
237: if (osm->sort_indices) {
238: for (i = 0; i < osm->n_local_true; i++) {
239: PetscCall(ISSort(osm->is[i]));
240: if (osm->is_local) PetscCall(ISSort(osm->is_local[i]));
241: }
242: }
243: flg = PETSC_FALSE;
244: PetscCall(PetscOptionsHasName(NULL, prefix, "-pc_asm_print_subdomains", &flg));
245: if (flg) PetscCall(PCASMPrintSubdomains(pc));
246: if (!osm->ksp) {
247: /* Create the local solvers */
248: PetscCall(PetscMalloc1(osm->n_local_true, &osm->ksp));
249: if (domain_dm) PetscCall(PetscInfo(pc, "Setting up ASM subproblems using the embedded DM\n"));
250: for (i = 0; i < osm->n_local_true; i++) {
251: PetscCall(KSPCreate(PETSC_COMM_SELF, &ksp));
252: PetscCall(KSPSetNestLevel(ksp, pc->kspnestlevel));
253: PetscCall(KSPSetErrorIfNotConverged(ksp, pc->erroriffailure));
254: PetscCall(PetscObjectIncrementTabLevel((PetscObject)ksp, (PetscObject)pc, 1));
255: PetscCall(KSPSetType(ksp, KSPPREONLY));
256: PetscCall(KSPGetPC(ksp, &subpc));
257: PetscCall(PCGetOptionsPrefix(pc, &prefix));
258: PetscCall(KSPSetOptionsPrefix(ksp, prefix));
259: PetscCall(KSPAppendOptionsPrefix(ksp, "sub_"));
260: if (domain_dm) {
261: PetscCall(KSPSetDM(ksp, domain_dm[i]));
262: PetscCall(KSPSetDMActive(ksp, KSP_DMACTIVE_ALL, PETSC_FALSE));
263: PetscCall(DMDestroy(&domain_dm[i]));
264: }
265: osm->ksp[i] = ksp;
266: }
267: PetscCall(PetscFree(domain_dm));
268: }
270: PetscCall(ISConcatenate(PETSC_COMM_SELF, osm->n_local_true, osm->is, &osm->lis));
271: PetscCall(ISSortRemoveDups(osm->lis));
272: PetscCall(ISGetLocalSize(osm->lis, &m));
274: scall = MAT_INITIAL_MATRIX;
275: } else {
276: /*
277: Destroy the blocks from the previous iteration
278: */
279: if (pc->flag == DIFFERENT_NONZERO_PATTERN) {
280: PetscCall(MatGetNullSpaces(osm->n_local_true, osm->pmat, &nullsp));
281: PetscCall(MatDestroyMatrices(osm->n_local_true, &osm->pmat));
282: scall = MAT_INITIAL_MATRIX;
283: }
284: }
286: /* Destroy previous submatrices of a different type than pc->pmat since MAT_REUSE_MATRIX won't work in that case */
287: if (scall == MAT_REUSE_MATRIX && osm->sub_mat_type) {
288: PetscCall(MatGetNullSpaces(osm->n_local_true, osm->pmat, &nullsp));
289: if (osm->n_local_true > 0) PetscCall(MatDestroySubMatrices(osm->n_local_true, &osm->pmat));
290: scall = MAT_INITIAL_MATRIX;
291: }
293: /*
294: Extract out the submatrices
295: */
296: PetscCall(MatCreateSubMatrices(pc->pmat, osm->n_local_true, osm->is, osm->is, scall, &osm->pmat));
297: if (scall == MAT_INITIAL_MATRIX) {
298: PetscCall(PetscObjectGetOptionsPrefix((PetscObject)pc->pmat, &pprefix));
299: for (i = 0; i < osm->n_local_true; i++) PetscCall(PetscObjectSetOptionsPrefix((PetscObject)osm->pmat[i], pprefix));
300: if (nullsp) PetscCall(MatRestoreNullSpaces(osm->n_local_true, osm->pmat, &nullsp));
301: }
303: /* Convert the types of the submatrices (if needbe) */
304: if (osm->sub_mat_type) {
305: for (i = 0; i < osm->n_local_true; i++) PetscCall(MatConvert(osm->pmat[i], osm->sub_mat_type, MAT_INPLACE_MATRIX, &osm->pmat[i]));
306: }
308: if (!pc->setupcalled) {
309: VecType vtype;
311: /* Create the local work vectors (from the local matrices) and scatter contexts */
312: PetscCall(MatCreateVecs(pc->pmat, &vec, NULL));
314: PetscCheck(!osm->is_local || osm->n_local_true == 1 || (osm->type != PC_ASM_INTERPOLATE && osm->type != PC_ASM_NONE), PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Cannot use interpolate or none PCASMType if is_local was provided to PCASMSetLocalSubdomains() with more than a single subdomain");
315: if (osm->is_local && osm->type != PC_ASM_BASIC && osm->loctype == PC_COMPOSITE_ADDITIVE) PetscCall(PetscMalloc1(osm->n_local_true, &osm->lprolongation));
316: PetscCall(PetscMalloc1(osm->n_local_true, &osm->lrestriction));
317: PetscCall(PetscMalloc1(osm->n_local_true, &osm->x));
318: PetscCall(PetscMalloc1(osm->n_local_true, &osm->y));
320: PetscCall(ISGetLocalSize(osm->lis, &m));
321: PetscCall(ISCreateStride(PETSC_COMM_SELF, m, 0, 1, &isl));
322: PetscCall(MatGetVecType(osm->pmat[0], &vtype));
323: PetscCall(VecCreate(PETSC_COMM_SELF, &osm->lx));
324: PetscCall(VecSetSizes(osm->lx, m, m));
325: PetscCall(VecSetType(osm->lx, vtype));
326: PetscCall(VecDuplicate(osm->lx, &osm->ly));
327: PetscCall(VecScatterCreate(vec, osm->lis, osm->lx, isl, &osm->restriction));
328: PetscCall(ISDestroy(&isl));
330: for (i = 0; i < osm->n_local_true; ++i) {
331: ISLocalToGlobalMapping ltog;
332: IS isll;
333: const PetscInt *idx_is;
334: PetscInt *idx_lis, nout;
336: PetscCall(ISGetLocalSize(osm->is[i], &m));
337: PetscCall(MatCreateVecs(osm->pmat[i], &osm->x[i], NULL));
338: PetscCall(VecDuplicate(osm->x[i], &osm->y[i]));
340: /* generate a scatter from ly to y[i] picking all the overlapping is[i] entries */
341: PetscCall(ISLocalToGlobalMappingCreateIS(osm->lis, <og));
342: PetscCall(ISGetLocalSize(osm->is[i], &m));
343: PetscCall(ISGetIndices(osm->is[i], &idx_is));
344: PetscCall(PetscMalloc1(m, &idx_lis));
345: PetscCall(ISGlobalToLocalMappingApply(ltog, IS_GTOLM_DROP, m, idx_is, &nout, idx_lis));
346: PetscCheck(nout == m, PETSC_COMM_SELF, PETSC_ERR_PLIB, "is not a subset of lis");
347: PetscCall(ISRestoreIndices(osm->is[i], &idx_is));
348: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m, idx_lis, PETSC_OWN_POINTER, &isll));
349: PetscCall(ISLocalToGlobalMappingDestroy(<og));
350: PetscCall(ISCreateStride(PETSC_COMM_SELF, m, 0, 1, &isl));
351: PetscCall(VecScatterCreate(osm->ly, isll, osm->y[i], isl, &osm->lrestriction[i]));
352: PetscCall(ISDestroy(&isll));
353: PetscCall(ISDestroy(&isl));
354: if (osm->lprolongation) { /* generate a scatter from y[i] to ly picking only the non-overlapping is_local[i] entries */
355: ISLocalToGlobalMapping ltog;
356: IS isll, isll_local;
357: const PetscInt *idx_local;
358: PetscInt *idx1, *idx2, nout;
360: PetscCall(ISGetLocalSize(osm->is_local[i], &m_local));
361: PetscCall(ISGetIndices(osm->is_local[i], &idx_local));
363: PetscCall(ISLocalToGlobalMappingCreateIS(osm->is[i], <og));
364: PetscCall(PetscMalloc1(m_local, &idx1));
365: PetscCall(ISGlobalToLocalMappingApply(ltog, IS_GTOLM_DROP, m_local, idx_local, &nout, idx1));
366: PetscCall(ISLocalToGlobalMappingDestroy(<og));
367: PetscCheck(nout == m_local, PETSC_COMM_SELF, PETSC_ERR_PLIB, "is_local not a subset of is");
368: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m_local, idx1, PETSC_OWN_POINTER, &isll));
370: PetscCall(ISLocalToGlobalMappingCreateIS(osm->lis, <og));
371: PetscCall(PetscMalloc1(m_local, &idx2));
372: PetscCall(ISGlobalToLocalMappingApply(ltog, IS_GTOLM_DROP, m_local, idx_local, &nout, idx2));
373: PetscCall(ISLocalToGlobalMappingDestroy(<og));
374: PetscCheck(nout == m_local, PETSC_COMM_SELF, PETSC_ERR_PLIB, "is_local not a subset of lis");
375: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, m_local, idx2, PETSC_OWN_POINTER, &isll_local));
377: PetscCall(ISRestoreIndices(osm->is_local[i], &idx_local));
378: PetscCall(VecScatterCreate(osm->y[i], isll, osm->ly, isll_local, &osm->lprolongation[i]));
380: PetscCall(ISDestroy(&isll));
381: PetscCall(ISDestroy(&isll_local));
382: }
383: }
384: PetscCall(VecDestroy(&vec));
385: }
387: if (osm->loctype == PC_COMPOSITE_MULTIPLICATIVE) {
388: IS *cis;
390: PetscCall(PetscMalloc1(osm->n_local_true, &cis));
391: for (PetscInt c = 0; c < osm->n_local_true; ++c) cis[c] = osm->lis;
392: PetscCall(MatCreateSubMatrices(pc->pmat, osm->n_local_true, osm->is, cis, scall, &osm->lmats));
393: PetscCall(PetscFree(cis));
394: }
396: /* Return control to the user so that the submatrices can be modified (e.g., to apply
397: different boundary conditions for the submatrices than for the global problem) */
398: PetscCall(PCModifySubMatrices(pc, osm->n_local_true, osm->is, osm->is, osm->pmat, pc->modifysubmatricesP));
400: /*
401: Loop over subdomains putting them into local ksp
402: */
403: PetscCall(KSPGetOptionsPrefix(osm->ksp[0], &prefix));
404: for (i = 0; i < osm->n_local_true; i++) {
405: PetscCall(KSPSetOperators(osm->ksp[i], osm->pmat[i], osm->pmat[i]));
406: PetscCall(MatSetOptionsPrefix(osm->pmat[i], prefix));
407: if (!pc->setupcalled) PetscCall(KSPSetFromOptions(osm->ksp[i]));
408: }
409: PetscFunctionReturn(PETSC_SUCCESS);
410: }
412: static PetscErrorCode PCSetUpOnBlocks_ASM(PC pc)
413: {
414: PC_ASM *osm = (PC_ASM *)pc->data;
415: PetscInt i;
416: KSPConvergedReason reason;
418: PetscFunctionBegin;
419: for (i = 0; i < osm->n_local_true; i++) {
420: PetscCall(KSPSetUp(osm->ksp[i]));
421: PetscCall(KSPGetConvergedReason(osm->ksp[i], &reason));
422: if (reason == KSP_DIVERGED_PC_FAILED) pc->failedreason = PC_SUBPC_ERROR;
423: }
424: PetscFunctionReturn(PETSC_SUCCESS);
425: }
427: static PetscErrorCode PCApply_ASM(PC pc, Vec x, Vec y)
428: {
429: PC_ASM *osm = (PC_ASM *)pc->data;
430: PetscInt i, n_local_true = osm->n_local_true;
431: ScatterMode forward = SCATTER_FORWARD, reverse = SCATTER_REVERSE;
433: PetscFunctionBegin;
434: /*
435: support for limiting the restriction or interpolation to only local
436: subdomain values (leaving the other values 0).
437: */
438: if (!(osm->type & PC_ASM_RESTRICT)) {
439: forward = SCATTER_FORWARD_LOCAL;
440: /* have to zero the work RHS since scatter may leave some slots empty */
441: PetscCall(VecSet(osm->lx, 0.0));
442: }
443: if (!(osm->type & PC_ASM_INTERPOLATE)) reverse = SCATTER_REVERSE_LOCAL;
445: PetscCheck(osm->loctype == PC_COMPOSITE_MULTIPLICATIVE || osm->loctype == PC_COMPOSITE_ADDITIVE, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONG, "Invalid local composition type: %s", PCCompositeTypes[osm->loctype]);
446: /* zero the global and the local solutions */
447: PetscCall(VecSet(y, 0.0));
448: PetscCall(VecSet(osm->ly, 0.0));
450: /* copy the global RHS to local RHS including the ghost nodes */
451: PetscCall(VecScatterBegin(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
452: PetscCall(VecScatterEnd(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
454: /* restrict local RHS to the overlapping 0-block RHS */
455: PetscCall(VecScatterBegin(osm->lrestriction[0], osm->lx, osm->x[0], INSERT_VALUES, forward));
456: PetscCall(VecScatterEnd(osm->lrestriction[0], osm->lx, osm->x[0], INSERT_VALUES, forward));
458: /* do the local solves */
459: for (i = 0; i < n_local_true; ++i) {
460: /* solve the overlapping i-block */
461: PetscCall(PetscLogEventBegin(PC_ApplyOnBlocks, osm->ksp[i], osm->x[i], osm->y[i], 0));
462: PetscCall(KSPSolve(osm->ksp[i], osm->x[i], osm->y[i]));
463: PetscCall(KSPCheckSolve(osm->ksp[i], pc, osm->y[i]));
464: PetscCall(PetscLogEventEnd(PC_ApplyOnBlocks, osm->ksp[i], osm->x[i], osm->y[i], 0));
466: if (osm->lprolongation && osm->type != PC_ASM_INTERPOLATE) { /* interpolate the non-overlapping i-block solution to the local solution (only for restrictive additive) */
467: PetscCall(VecScatterBegin(osm->lprolongation[i], osm->y[i], osm->ly, ADD_VALUES, forward));
468: PetscCall(VecScatterEnd(osm->lprolongation[i], osm->y[i], osm->ly, ADD_VALUES, forward));
469: } else { /* interpolate the overlapping i-block solution to the local solution */
470: PetscCall(VecScatterBegin(osm->lrestriction[i], osm->y[i], osm->ly, ADD_VALUES, reverse));
471: PetscCall(VecScatterEnd(osm->lrestriction[i], osm->y[i], osm->ly, ADD_VALUES, reverse));
472: }
474: if (i < n_local_true - 1) {
475: /* restrict local RHS to the overlapping (i+1)-block RHS */
476: PetscCall(VecScatterBegin(osm->lrestriction[i + 1], osm->lx, osm->x[i + 1], INSERT_VALUES, forward));
477: PetscCall(VecScatterEnd(osm->lrestriction[i + 1], osm->lx, osm->x[i + 1], INSERT_VALUES, forward));
479: if (osm->loctype == PC_COMPOSITE_MULTIPLICATIVE) {
480: /* update the overlapping (i+1)-block RHS using the current local solution */
481: PetscCall(MatMult(osm->lmats[i + 1], osm->ly, osm->y[i + 1]));
482: PetscCall(VecAXPBY(osm->x[i + 1], -1., 1., osm->y[i + 1]));
483: }
484: }
485: }
486: /* add the local solution to the global solution including the ghost nodes */
487: PetscCall(VecScatterBegin(osm->restriction, osm->ly, y, ADD_VALUES, reverse));
488: PetscCall(VecScatterEnd(osm->restriction, osm->ly, y, ADD_VALUES, reverse));
489: PetscFunctionReturn(PETSC_SUCCESS);
490: }
492: static PetscErrorCode PCMatApply_ASM_Private(PC pc, Mat X, Mat Y, PetscBool transpose)
493: {
494: PC_ASM *osm = (PC_ASM *)pc->data;
495: Mat Z, W;
496: Vec x;
497: PetscInt i, m, N;
498: ScatterMode forward = SCATTER_FORWARD, reverse = SCATTER_REVERSE;
500: PetscFunctionBegin;
501: PetscCheck(osm->n_local_true <= 1, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Not yet implemented");
502: /*
503: support for limiting the restriction or interpolation to only local
504: subdomain values (leaving the other values 0).
505: */
506: if ((!transpose && !(osm->type & PC_ASM_RESTRICT)) || (transpose && !(osm->type & PC_ASM_INTERPOLATE))) {
507: forward = SCATTER_FORWARD_LOCAL;
508: /* have to zero the work RHS since scatter may leave some slots empty */
509: PetscCall(VecSet(osm->lx, 0.0));
510: }
511: if ((!transpose && !(osm->type & PC_ASM_INTERPOLATE)) || (transpose && !(osm->type & PC_ASM_RESTRICT))) reverse = SCATTER_REVERSE_LOCAL;
512: PetscCall(VecGetLocalSize(osm->x[0], &m));
513: PetscCall(MatGetSize(X, NULL, &N));
514: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF, m, N, NULL, &Z));
516: PetscCheck(osm->loctype == PC_COMPOSITE_MULTIPLICATIVE || osm->loctype == PC_COMPOSITE_ADDITIVE, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONG, "Invalid local composition type: %s", PCCompositeTypes[osm->loctype]);
517: /* zero the global and the local solutions */
518: PetscCall(MatZeroEntries(Y));
519: PetscCall(VecSet(osm->ly, 0.0));
521: for (i = 0; i < N; ++i) {
522: PetscCall(MatDenseGetColumnVecRead(X, i, &x));
523: /* copy the global RHS to local RHS including the ghost nodes */
524: PetscCall(VecScatterBegin(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
525: PetscCall(VecScatterEnd(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
526: PetscCall(MatDenseRestoreColumnVecRead(X, i, &x));
528: PetscCall(MatDenseGetColumnVecWrite(Z, i, &x));
529: /* restrict local RHS to the overlapping 0-block RHS */
530: PetscCall(VecScatterBegin(osm->lrestriction[0], osm->lx, x, INSERT_VALUES, forward));
531: PetscCall(VecScatterEnd(osm->lrestriction[0], osm->lx, x, INSERT_VALUES, forward));
532: PetscCall(MatDenseRestoreColumnVecWrite(Z, i, &x));
533: }
534: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF, m, N, NULL, &W));
535: /* solve the overlapping 0-block */
536: if (!transpose) {
537: PetscCall(PetscLogEventBegin(PC_ApplyOnBlocks, osm->ksp[0], Z, W, 0));
538: PetscCall(KSPMatSolve(osm->ksp[0], Z, W));
539: PetscCall(PetscLogEventEnd(PC_ApplyOnBlocks, osm->ksp[0], Z, W, 0));
540: } else {
541: PetscCall(PetscLogEventBegin(PC_ApplyTransposeOnBlocks, osm->ksp[0], Z, W, 0));
542: PetscCall(KSPMatSolveTranspose(osm->ksp[0], Z, W));
543: PetscCall(PetscLogEventEnd(PC_ApplyTransposeOnBlocks, osm->ksp[0], Z, W, 0));
544: }
545: PetscCall(KSPCheckSolve(osm->ksp[0], pc, NULL));
546: PetscCall(MatDestroy(&Z));
548: for (i = 0; i < N; ++i) {
549: PetscCall(VecSet(osm->ly, 0.0));
550: PetscCall(MatDenseGetColumnVecRead(W, i, &x));
551: if (osm->lprolongation && ((!transpose && osm->type != PC_ASM_INTERPOLATE) || (transpose && osm->type != PC_ASM_RESTRICT))) { /* interpolate the non-overlapping 0-block solution to the local solution (only for restrictive additive) */
552: PetscCall(VecScatterBegin(osm->lprolongation[0], x, osm->ly, ADD_VALUES, forward));
553: PetscCall(VecScatterEnd(osm->lprolongation[0], x, osm->ly, ADD_VALUES, forward));
554: } else { /* interpolate the overlapping 0-block solution to the local solution */
555: PetscCall(VecScatterBegin(osm->lrestriction[0], x, osm->ly, ADD_VALUES, reverse));
556: PetscCall(VecScatterEnd(osm->lrestriction[0], x, osm->ly, ADD_VALUES, reverse));
557: }
558: PetscCall(MatDenseRestoreColumnVecRead(W, i, &x));
560: PetscCall(MatDenseGetColumnVecWrite(Y, i, &x));
561: /* add the local solution to the global solution including the ghost nodes */
562: PetscCall(VecScatterBegin(osm->restriction, osm->ly, x, ADD_VALUES, reverse));
563: PetscCall(VecScatterEnd(osm->restriction, osm->ly, x, ADD_VALUES, reverse));
564: PetscCall(MatDenseRestoreColumnVecWrite(Y, i, &x));
565: }
566: PetscCall(MatDestroy(&W));
567: PetscFunctionReturn(PETSC_SUCCESS);
568: }
570: static PetscErrorCode PCMatApply_ASM(PC pc, Mat X, Mat Y)
571: {
572: PetscFunctionBegin;
573: PetscCall(PCMatApply_ASM_Private(pc, X, Y, PETSC_FALSE));
574: PetscFunctionReturn(PETSC_SUCCESS);
575: }
577: static PetscErrorCode PCMatApplyTranspose_ASM(PC pc, Mat X, Mat Y)
578: {
579: PetscFunctionBegin;
580: PetscCall(PCMatApply_ASM_Private(pc, X, Y, PETSC_TRUE));
581: PetscFunctionReturn(PETSC_SUCCESS);
582: }
584: static PetscErrorCode PCApplyTranspose_ASM(PC pc, Vec x, Vec y)
585: {
586: PC_ASM *osm = (PC_ASM *)pc->data;
587: PetscInt i, n_local_true = osm->n_local_true;
588: ScatterMode forward = SCATTER_FORWARD, reverse = SCATTER_REVERSE;
590: PetscFunctionBegin;
591: PetscCheck(osm->n_local_true <= 1 || osm->loctype == PC_COMPOSITE_ADDITIVE, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Not yet implemented");
592: /*
593: Support for limiting the restriction or interpolation to only local
594: subdomain values (leaving the other values 0).
596: Note: these are reversed from the PCApply_ASM() because we are applying the
597: transpose of the three terms
598: */
600: if (!(osm->type & PC_ASM_INTERPOLATE)) {
601: forward = SCATTER_FORWARD_LOCAL;
602: /* have to zero the work RHS since scatter may leave some slots empty */
603: PetscCall(VecSet(osm->lx, 0.0));
604: }
605: if (!(osm->type & PC_ASM_RESTRICT)) reverse = SCATTER_REVERSE_LOCAL;
607: /* zero the global and the local solutions */
608: PetscCall(VecSet(y, 0.0));
609: PetscCall(VecSet(osm->ly, 0.0));
611: /* Copy the global RHS to local RHS including the ghost nodes */
612: PetscCall(VecScatterBegin(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
613: PetscCall(VecScatterEnd(osm->restriction, x, osm->lx, INSERT_VALUES, forward));
615: /* Restrict local RHS to the overlapping 0-block RHS */
616: PetscCall(VecScatterBegin(osm->lrestriction[0], osm->lx, osm->x[0], INSERT_VALUES, forward));
617: PetscCall(VecScatterEnd(osm->lrestriction[0], osm->lx, osm->x[0], INSERT_VALUES, forward));
619: /* do the local solves */
620: for (i = 0; i < n_local_true; ++i) {
621: /* solve the overlapping i-block */
622: PetscCall(PetscLogEventBegin(PC_ApplyTransposeOnBlocks, osm->ksp[i], osm->x[i], osm->y[i], 0));
623: PetscCall(KSPSolveTranspose(osm->ksp[i], osm->x[i], osm->y[i]));
624: PetscCall(KSPCheckSolve(osm->ksp[i], pc, osm->y[i]));
625: PetscCall(PetscLogEventEnd(PC_ApplyTransposeOnBlocks, osm->ksp[i], osm->x[i], osm->y[i], 0));
627: if (osm->lprolongation && osm->type != PC_ASM_RESTRICT) { /* interpolate the non-overlapping i-block solution to the local solution */
628: PetscCall(VecScatterBegin(osm->lprolongation[i], osm->y[i], osm->ly, ADD_VALUES, forward));
629: PetscCall(VecScatterEnd(osm->lprolongation[i], osm->y[i], osm->ly, ADD_VALUES, forward));
630: } else { /* interpolate the overlapping i-block solution to the local solution */
631: PetscCall(VecScatterBegin(osm->lrestriction[i], osm->y[i], osm->ly, ADD_VALUES, reverse));
632: PetscCall(VecScatterEnd(osm->lrestriction[i], osm->y[i], osm->ly, ADD_VALUES, reverse));
633: }
635: if (i < n_local_true - 1) {
636: /* Restrict local RHS to the overlapping (i+1)-block RHS */
637: PetscCall(VecScatterBegin(osm->lrestriction[i + 1], osm->lx, osm->x[i + 1], INSERT_VALUES, forward));
638: PetscCall(VecScatterEnd(osm->lrestriction[i + 1], osm->lx, osm->x[i + 1], INSERT_VALUES, forward));
639: }
640: }
641: /* Add the local solution to the global solution including the ghost nodes */
642: PetscCall(VecScatterBegin(osm->restriction, osm->ly, y, ADD_VALUES, reverse));
643: PetscCall(VecScatterEnd(osm->restriction, osm->ly, y, ADD_VALUES, reverse));
644: PetscFunctionReturn(PETSC_SUCCESS);
645: }
647: static PetscErrorCode PCReset_ASM(PC pc)
648: {
649: PC_ASM *osm = (PC_ASM *)pc->data;
651: PetscFunctionBegin;
652: if (osm->ksp) {
653: for (PetscInt i = 0; i < osm->n_local_true; i++) PetscCall(KSPReset(osm->ksp[i]));
654: }
655: if (osm->pmat) {
656: if (osm->n_local_true > 0) PetscCall(MatDestroySubMatrices(osm->n_local_true, &osm->pmat));
657: }
658: if (osm->lrestriction) {
659: PetscCall(VecScatterDestroy(&osm->restriction));
660: for (PetscInt i = 0; i < osm->n_local_true; i++) {
661: PetscCall(VecScatterDestroy(&osm->lrestriction[i]));
662: if (osm->lprolongation) PetscCall(VecScatterDestroy(&osm->lprolongation[i]));
663: PetscCall(VecDestroy(&osm->x[i]));
664: PetscCall(VecDestroy(&osm->y[i]));
665: }
666: PetscCall(PetscFree(osm->lrestriction));
667: PetscCall(PetscFree(osm->lprolongation));
668: PetscCall(PetscFree(osm->x));
669: PetscCall(PetscFree(osm->y));
670: }
671: PetscCall(PCASMDestroySubdomains(osm->n_local_true, &osm->is, &osm->is_local));
672: PetscCall(ISDestroy(&osm->lis));
673: PetscCall(VecDestroy(&osm->lx));
674: PetscCall(VecDestroy(&osm->ly));
675: if (osm->loctype == PC_COMPOSITE_MULTIPLICATIVE) PetscCall(MatDestroyMatrices(osm->n_local_true, &osm->lmats));
677: PetscCall(PetscFree(osm->sub_mat_type));
679: osm->is = NULL;
680: osm->is_local = NULL;
681: PetscFunctionReturn(PETSC_SUCCESS);
682: }
684: static PetscErrorCode PCDestroy_ASM(PC pc)
685: {
686: PC_ASM *osm = (PC_ASM *)pc->data;
688: PetscFunctionBegin;
689: PetscCall(PCReset_ASM(pc));
690: if (osm->ksp) {
691: for (PetscInt i = 0; i < osm->n_local_true; i++) PetscCall(KSPDestroy(&osm->ksp[i]));
692: PetscCall(PetscFree(osm->ksp));
693: }
694: PetscCall(PetscFree(pc->data));
696: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetLocalSubdomains_C", NULL));
697: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetTotalSubdomains_C", NULL));
698: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetOverlap_C", NULL));
699: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetType_C", NULL));
700: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetType_C", NULL));
701: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetLocalType_C", NULL));
702: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetLocalType_C", NULL));
703: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetSortIndices_C", NULL));
704: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetSubKSP_C", NULL));
705: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetSubMatType_C", NULL));
706: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetSubMatType_C", NULL));
707: PetscFunctionReturn(PETSC_SUCCESS);
708: }
710: static PetscErrorCode PCSetFromOptions_ASM(PC pc, PetscOptionItems PetscOptionsObject)
711: {
712: PC_ASM *osm = (PC_ASM *)pc->data;
713: PetscInt blocks, ovl;
714: PetscBool flg;
715: PCASMType asmtype;
716: PCCompositeType loctype;
717: char sub_mat_type[256];
719: PetscFunctionBegin;
720: PetscOptionsHeadBegin(PetscOptionsObject, "Additive Schwarz options");
721: PetscCall(PetscOptionsBool("-pc_asm_dm_subdomains", "Use DMCreateDomainDecomposition() to define subdomains", "PCASMSetDMSubdomains", osm->dm_subdomains, &osm->dm_subdomains, &flg));
722: PetscCall(PetscOptionsInt("-pc_asm_blocks", "Number of subdomains", "PCASMSetTotalSubdomains", osm->n, &blocks, &flg));
723: if (flg) {
724: PetscCall(PCASMSetTotalSubdomains(pc, blocks, NULL, NULL));
725: osm->dm_subdomains = PETSC_FALSE;
726: }
727: PetscCall(PetscOptionsInt("-pc_asm_local_blocks", "Number of local subdomains", "PCASMSetLocalSubdomains", osm->n_local_true, &blocks, &flg));
728: if (flg) {
729: PetscCall(PCASMSetLocalSubdomains(pc, blocks, NULL, NULL));
730: osm->dm_subdomains = PETSC_FALSE;
731: }
732: PetscCall(PetscOptionsInt("-pc_asm_overlap", "Number of grid points overlap", "PCASMSetOverlap", osm->overlap, &ovl, &flg));
733: if (flg) {
734: PetscCall(PCASMSetOverlap(pc, ovl));
735: osm->dm_subdomains = PETSC_FALSE;
736: }
737: flg = PETSC_FALSE;
738: PetscCall(PetscOptionsEnum("-pc_asm_type", "Type of restriction/extension", "PCASMSetType", PCASMTypes, (PetscEnum)osm->type, (PetscEnum *)&asmtype, &flg));
739: if (flg) PetscCall(PCASMSetType(pc, asmtype));
740: flg = PETSC_FALSE;
741: PetscCall(PetscOptionsEnum("-pc_asm_local_type", "Type of local solver composition", "PCASMSetLocalType", PCCompositeTypes, (PetscEnum)osm->loctype, (PetscEnum *)&loctype, &flg));
742: if (flg) PetscCall(PCASMSetLocalType(pc, loctype));
743: PetscCall(PetscOptionsFList("-pc_asm_sub_mat_type", "Subsolve Matrix Type", "PCASMSetSubMatType", MatList, NULL, sub_mat_type, 256, &flg));
744: if (flg) PetscCall(PCASMSetSubMatType(pc, sub_mat_type));
745: PetscOptionsHeadEnd();
746: PetscFunctionReturn(PETSC_SUCCESS);
747: }
749: static PetscErrorCode PCASMSetLocalSubdomains_ASM(PC pc, PetscInt n, IS is[], IS is_local[])
750: {
751: PC_ASM *osm = (PC_ASM *)pc->data;
753: PetscFunctionBegin;
754: PetscCheck(n >= 1, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Each process must have 1 or more blocks, n = %" PetscInt_FMT, n);
755: PetscCheck(!pc->setupcalled || (n == osm->n_local_true && !is), PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONGSTATE, "PCASMSetLocalSubdomains() should be called before calling PCSetUp().");
757: if (!pc->setupcalled) {
758: if (is) {
759: for (PetscInt i = 0; i < n; i++) PetscCall(PetscObjectReference((PetscObject)is[i]));
760: }
761: if (is_local) {
762: for (PetscInt i = 0; i < n; i++) PetscCall(PetscObjectReference((PetscObject)is_local[i]));
763: }
764: PetscCall(PCASMDestroySubdomains(osm->n_local_true, &osm->is, &osm->is_local));
766: if (osm->ksp && osm->n_local_true != n) {
767: for (PetscInt i = 0; i < osm->n_local_true; i++) PetscCall(KSPDestroy(&osm->ksp[i]));
768: PetscCall(PetscFree(osm->ksp));
769: }
771: osm->n_local_true = n;
772: osm->is = NULL;
773: osm->is_local = NULL;
774: if (is) {
775: PetscCall(PetscMalloc1(n, &osm->is));
776: for (PetscInt i = 0; i < n; i++) osm->is[i] = is[i];
777: /* Flag indicating that the user has set overlapping subdomains so PCASM should not increase their size. */
778: osm->overlap = -1;
779: }
780: if (is_local) {
781: PetscCall(PetscMalloc1(n, &osm->is_local));
782: for (PetscInt i = 0; i < n; i++) osm->is_local[i] = is_local[i];
783: if (!is) {
784: PetscCall(PetscMalloc1(osm->n_local_true, &osm->is));
785: for (PetscInt i = 0; i < osm->n_local_true; i++) {
786: if (osm->overlap > 0) { /* With positive overlap, osm->is[i] will be modified */
787: PetscCall(ISDuplicate(osm->is_local[i], &osm->is[i]));
788: PetscCall(ISCopy(osm->is_local[i], osm->is[i]));
789: } else {
790: PetscCall(PetscObjectReference((PetscObject)osm->is_local[i]));
791: osm->is[i] = osm->is_local[i];
792: }
793: }
794: }
795: }
796: }
797: PetscFunctionReturn(PETSC_SUCCESS);
798: }
800: static PetscErrorCode PCASMSetTotalSubdomains_ASM(PC pc, PetscInt N, IS *is, IS *is_local)
801: {
802: PC_ASM *osm = (PC_ASM *)pc->data;
803: PetscMPIInt rank, size;
804: PetscInt n;
806: PetscFunctionBegin;
807: PetscCheck(N >= 1, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_OUTOFRANGE, "Number of total blocks must be > 0, N = %" PetscInt_FMT, N);
808: PetscCheck(!is && !is_local, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Use PCASMSetLocalSubdomains() to set specific index sets, they cannot be set globally yet.");
810: /*
811: Split the subdomains equally among all processors
812: */
813: PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc), &rank));
814: PetscCallMPI(MPI_Comm_size(PetscObjectComm((PetscObject)pc), &size));
815: n = N / size + ((N % size) > rank);
816: PetscCheck(n, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Process %d must have at least one block: total processors %d total blocks %" PetscInt_FMT, rank, size, N);
817: PetscCheck(!pc->setupcalled || n == osm->n_local_true, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "PCASMSetTotalSubdomains() should be called before PCSetUp().");
818: if (!pc->setupcalled) {
819: PetscCall(PCASMDestroySubdomains(osm->n_local_true, &osm->is, &osm->is_local));
821: osm->n_local_true = n;
822: osm->is = NULL;
823: osm->is_local = NULL;
824: }
825: PetscFunctionReturn(PETSC_SUCCESS);
826: }
828: static PetscErrorCode PCASMSetOverlap_ASM(PC pc, PetscInt ovl)
829: {
830: PC_ASM *osm = (PC_ASM *)pc->data;
832: PetscFunctionBegin;
833: PetscCheck(ovl >= 0, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_OUTOFRANGE, "Negative overlap value requested");
834: PetscCheck(!pc->setupcalled || ovl == osm->overlap, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONGSTATE, "PCASMSetOverlap() should be called before PCSetUp().");
835: if (!pc->setupcalled) osm->overlap = ovl;
836: PetscFunctionReturn(PETSC_SUCCESS);
837: }
839: static PetscErrorCode PCASMSetType_ASM(PC pc, PCASMType type)
840: {
841: PC_ASM *osm = (PC_ASM *)pc->data;
843: PetscFunctionBegin;
844: osm->type = type;
845: osm->type_set = PETSC_TRUE;
846: PetscFunctionReturn(PETSC_SUCCESS);
847: }
849: static PetscErrorCode PCASMGetType_ASM(PC pc, PCASMType *type)
850: {
851: PC_ASM *osm = (PC_ASM *)pc->data;
853: PetscFunctionBegin;
854: *type = osm->type;
855: PetscFunctionReturn(PETSC_SUCCESS);
856: }
858: static PetscErrorCode PCASMSetLocalType_ASM(PC pc, PCCompositeType type)
859: {
860: PC_ASM *osm = (PC_ASM *)pc->data;
862: PetscFunctionBegin;
863: PetscCheck(type == PC_COMPOSITE_ADDITIVE || type == PC_COMPOSITE_MULTIPLICATIVE, PetscObjectComm((PetscObject)pc), PETSC_ERR_SUP, "Only supports additive or multiplicative as the local type");
864: osm->loctype = type;
865: PetscFunctionReturn(PETSC_SUCCESS);
866: }
868: static PetscErrorCode PCASMGetLocalType_ASM(PC pc, PCCompositeType *type)
869: {
870: PC_ASM *osm = (PC_ASM *)pc->data;
872: PetscFunctionBegin;
873: *type = osm->loctype;
874: PetscFunctionReturn(PETSC_SUCCESS);
875: }
877: static PetscErrorCode PCASMSetSortIndices_ASM(PC pc, PetscBool doSort)
878: {
879: PC_ASM *osm = (PC_ASM *)pc->data;
881: PetscFunctionBegin;
882: osm->sort_indices = doSort;
883: PetscFunctionReturn(PETSC_SUCCESS);
884: }
886: static PetscErrorCode PCASMGetSubKSP_ASM(PC pc, PetscInt *n_local, PetscInt *first_local, KSP **ksp)
887: {
888: PC_ASM *osm = (PC_ASM *)pc->data;
890: PetscFunctionBegin;
891: PetscCheck(osm->n_local_true >= 1, PetscObjectComm((PetscObject)pc), PETSC_ERR_ORDER, "Need to call PCSetUp() on PC (or KSPSetUp() on the outer KSP object) before calling here");
893: if (n_local) *n_local = osm->n_local_true;
894: if (first_local) {
895: PetscCallMPI(MPI_Scan(&osm->n_local_true, first_local, 1, MPIU_INT, MPI_SUM, PetscObjectComm((PetscObject)pc)));
896: *first_local -= osm->n_local_true;
897: }
898: if (ksp) *ksp = osm->ksp;
899: PetscFunctionReturn(PETSC_SUCCESS);
900: }
902: static PetscErrorCode PCASMGetSubMatType_ASM(PC pc, MatType *sub_mat_type)
903: {
904: PC_ASM *osm = (PC_ASM *)pc->data;
906: PetscFunctionBegin;
908: PetscAssertPointer(sub_mat_type, 2);
909: *sub_mat_type = osm->sub_mat_type;
910: PetscFunctionReturn(PETSC_SUCCESS);
911: }
913: static PetscErrorCode PCASMSetSubMatType_ASM(PC pc, MatType sub_mat_type)
914: {
915: PC_ASM *osm = (PC_ASM *)pc->data;
917: PetscFunctionBegin;
919: PetscCall(PetscFree(osm->sub_mat_type));
920: PetscCall(PetscStrallocpy(sub_mat_type, (char **)&osm->sub_mat_type));
921: PetscFunctionReturn(PETSC_SUCCESS);
922: }
924: /*@
925: PCASMSetLocalSubdomains - Sets the local subdomains (for this processor only) for the additive Schwarz preconditioner `PCASM`.
927: Collective
929: Input Parameters:
930: + pc - the preconditioner context
931: . n - the number of subdomains for this processor (default value = 1)
932: . is - the index set that defines the subdomains for this processor (or `NULL` for PETSc to determine subdomains)
933: the values of the `is` array are copied so you can free the array (not the `IS` in the array) after this call
934: - is_local - the index sets that define the local part of the subdomains for this processor, not used unless `PCASMType` is `PC_ASM_RESTRICT`
935: (or `NULL` to not provide these). The values of the `is_local` array are copied so you can free the array
936: (not the `IS` in the array) after this call
938: Options Database Key:
939: . -pc_asm_local_blocks blks - Sets number of local blocks
941: Level: advanced
943: Notes:
944: The `IS` numbering is in the parallel, global numbering of the vector for both `is` and `is_local`
946: By default the `PCASM` preconditioner uses 1 block per processor.
948: Use `PCASMSetTotalSubdomains()` to set the subdomains for all processors.
950: If `is_local` is provided and `PCASMType` is `PC_ASM_RESTRICT` then the solution only over the `is_local` region is interpolated
951: back to form the global solution (this is the standard restricted additive Schwarz method, RASM)
953: If `is_local` is provided and `PCASMType` is `PC_ASM_INTERPOLATE` or `PC_ASM_NONE` then an error is generated since there is
954: no code to handle that case.
956: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`, `PCASMGetSubKSP()`,
957: `PCASMCreateSubdomains2D()`, `PCASMGetLocalSubdomains()`, `PCASMType`, `PCASMSetType()`, `PCGASM`
958: @*/
959: PetscErrorCode PCASMSetLocalSubdomains(PC pc, PetscInt n, IS is[], IS is_local[])
960: {
961: PetscFunctionBegin;
963: PetscTryMethod(pc, "PCASMSetLocalSubdomains_C", (PC, PetscInt, IS[], IS[]), (pc, n, is, is_local));
964: PetscFunctionReturn(PETSC_SUCCESS);
965: }
967: /*@
968: PCASMSetTotalSubdomains - Sets the subdomains for all processors for the
969: additive Schwarz preconditioner, `PCASM`.
971: Collective, all MPI ranks must pass in the same array of `IS`
973: Input Parameters:
974: + pc - the preconditioner context
975: . N - the number of subdomains for all processors
976: . is - the index sets that define the subdomains for all processors (or `NULL` to ask PETSc to determine the subdomains)
977: the values of the `is` array are copied so you can free the array (not the `IS` in the array) after this call
978: - is_local - the index sets that define the local part of the subdomains for this processor (or `NULL` to not provide this information)
979: The values of the `is_local` array are copied so you can free the array (not the `IS` in the array) after this call
981: Options Database Key:
982: . -pc_asm_blocks blks - Sets total blocks
984: Level: advanced
986: Notes:
987: Currently you cannot use this to set the actual subdomains with the argument `is` or `is_local`.
989: By default the `PCASM` preconditioner uses 1 block per processor.
991: These index sets cannot be destroyed until after completion of the
992: linear solves for which the `PCASM` preconditioner is being used.
994: Use `PCASMSetLocalSubdomains()` to set local subdomains.
996: The `IS` numbering is in the parallel, global numbering of the vector for both is and is_local
998: .seealso: [](ch_ksp), `PCASM`, `PCASMSetLocalSubdomains()`, `PCASMSetOverlap()`, `PCASMGetSubKSP()`,
999: `PCASMCreateSubdomains2D()`, `PCGASM`
1000: @*/
1001: PetscErrorCode PCASMSetTotalSubdomains(PC pc, PetscInt N, IS is[], IS is_local[])
1002: {
1003: PetscFunctionBegin;
1005: PetscTryMethod(pc, "PCASMSetTotalSubdomains_C", (PC, PetscInt, IS[], IS[]), (pc, N, is, is_local));
1006: PetscFunctionReturn(PETSC_SUCCESS);
1007: }
1009: /*@
1010: PCASMSetOverlap - Sets the overlap between a pair of subdomains for the
1011: additive Schwarz preconditioner, `PCASM`.
1013: Logically Collective
1015: Input Parameters:
1016: + pc - the preconditioner context
1017: - ovl - the amount of overlap between subdomains (ovl >= 0, default value = 1)
1019: Options Database Key:
1020: . -pc_asm_overlap ovl - Sets overlap
1022: Level: intermediate
1024: Notes:
1025: By default the `PCASM` preconditioner uses 1 block per processor. To use
1026: multiple blocks per perocessor, see `PCASMSetTotalSubdomains()` and
1027: `PCASMSetLocalSubdomains()` (and the option -pc_asm_blocks <blks>).
1029: The overlap defaults to 1, so if one desires that no additional
1030: overlap be computed beyond what may have been set with a call to
1031: `PCASMSetTotalSubdomains()` or `PCASMSetLocalSubdomains()`, then ovl
1032: must be set to be 0. In particular, if one does not explicitly set
1033: the subdomains an application code, then all overlap would be computed
1034: internally by PETSc, and using an overlap of 0 would result in an `PCASM`
1035: variant that is equivalent to the block Jacobi preconditioner.
1037: The default algorithm used by PETSc to increase overlap is fast, but not scalable,
1038: use the option -mat_increase_overlap_scalable when the problem and number of processes is large.
1040: One can define initial index sets with any overlap via
1041: `PCASMSetLocalSubdomains()`; the routine
1042: `PCASMSetOverlap()` merely allows PETSc to extend that overlap further
1043: if desired.
1045: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetLocalSubdomains()`, `PCASMGetSubKSP()`,
1046: `PCASMCreateSubdomains2D()`, `PCASMGetLocalSubdomains()`, `MatIncreaseOverlap()`, `PCGASM`
1047: @*/
1048: PetscErrorCode PCASMSetOverlap(PC pc, PetscInt ovl)
1049: {
1050: PetscFunctionBegin;
1053: PetscTryMethod(pc, "PCASMSetOverlap_C", (PC, PetscInt), (pc, ovl));
1054: PetscFunctionReturn(PETSC_SUCCESS);
1055: }
1057: /*@
1058: PCASMSetType - Sets the type of restriction and interpolation used
1059: for local problems in the additive Schwarz method, `PCASM`.
1061: Logically Collective
1063: Input Parameters:
1064: + pc - the preconditioner context
1065: - type - variant of `PCASM`, one of
1066: .vb
1067: PC_ASM_BASIC - full interpolation and restriction
1068: PC_ASM_RESTRICT - full restriction, local processor interpolation (default)
1069: PC_ASM_INTERPOLATE - full interpolation, local processor restriction
1070: PC_ASM_NONE - local processor restriction and interpolation
1071: .ve
1073: Options Database Key:
1074: . -pc_asm_type [basic,restrict,interpolate,none] - Sets `PCASMType`
1076: Level: intermediate
1078: Note:
1079: if the is_local arguments are passed to `PCASMSetLocalSubdomains()` then they are used when `PC_ASM_RESTRICT` has been selected
1080: to limit the local processor interpolation
1082: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMGetSubKSP()`,
1083: `PCASMCreateSubdomains2D()`, `PCASMType`, `PCASMSetLocalType()`, `PCASMGetLocalType()`, `PCGASM`
1084: @*/
1085: PetscErrorCode PCASMSetType(PC pc, PCASMType type)
1086: {
1087: PetscFunctionBegin;
1090: PetscTryMethod(pc, "PCASMSetType_C", (PC, PCASMType), (pc, type));
1091: PetscFunctionReturn(PETSC_SUCCESS);
1092: }
1094: /*@
1095: PCASMGetType - Gets the type of restriction and interpolation used
1096: for local problems in the additive Schwarz method, `PCASM`.
1098: Logically Collective
1100: Input Parameter:
1101: . pc - the preconditioner context
1103: Output Parameter:
1104: . type - variant of `PCASM`, one of
1105: .vb
1106: PC_ASM_BASIC - full interpolation and restriction
1107: PC_ASM_RESTRICT - full restriction, local processor interpolation
1108: PC_ASM_INTERPOLATE - full interpolation, local processor restriction
1109: PC_ASM_NONE - local processor restriction and interpolation
1110: .ve
1112: Options Database Key:
1113: . -pc_asm_type [basic,restrict,interpolate,none] - Sets `PCASM` type
1115: Level: intermediate
1117: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMGetSubKSP()`, `PCGASM`,
1118: `PCASMCreateSubdomains2D()`, `PCASMType`, `PCASMSetType()`, `PCASMSetLocalType()`, `PCASMGetLocalType()`
1119: @*/
1120: PetscErrorCode PCASMGetType(PC pc, PCASMType *type)
1121: {
1122: PetscFunctionBegin;
1124: PetscUseMethod(pc, "PCASMGetType_C", (PC, PCASMType *), (pc, type));
1125: PetscFunctionReturn(PETSC_SUCCESS);
1126: }
1128: /*@
1129: PCASMSetLocalType - Sets the type of composition used for local problems in the additive Schwarz method, `PCASM`.
1131: Logically Collective
1133: Input Parameters:
1134: + pc - the preconditioner context
1135: - type - type of composition, one of
1136: .vb
1137: PC_COMPOSITE_ADDITIVE - local additive combination
1138: PC_COMPOSITE_MULTIPLICATIVE - local multiplicative combination
1139: .ve
1141: Options Database Key:
1142: . -pc_asm_local_type [additive,multiplicative] - Sets local solver composition type
1144: Level: intermediate
1146: .seealso: [](ch_ksp), `PCASM`, `PCASMSetType()`, `PCASMGetType()`, `PCASMGetLocalType()`, `PCASMType`, `PCCompositeType`
1147: @*/
1148: PetscErrorCode PCASMSetLocalType(PC pc, PCCompositeType type)
1149: {
1150: PetscFunctionBegin;
1153: PetscTryMethod(pc, "PCASMSetLocalType_C", (PC, PCCompositeType), (pc, type));
1154: PetscFunctionReturn(PETSC_SUCCESS);
1155: }
1157: /*@
1158: PCASMGetLocalType - Gets the type of composition used for local problems in the additive Schwarz method, `PCASM`.
1160: Logically Collective
1162: Input Parameter:
1163: . pc - the preconditioner context
1165: Output Parameter:
1166: . type - type of composition, one of
1167: .vb
1168: PC_COMPOSITE_ADDITIVE - local additive combination
1169: PC_COMPOSITE_MULTIPLICATIVE - local multiplicative combination
1170: .ve
1172: Options Database Key:
1173: . -pc_asm_local_type [additive,multiplicative] - Sets local solver composition type
1175: Level: intermediate
1177: .seealso: [](ch_ksp), `PCASM`, `PCASMSetType()`, `PCASMGetType()`, `PCASMSetLocalType()`, `PCASMType`, `PCCompositeType`
1178: @*/
1179: PetscErrorCode PCASMGetLocalType(PC pc, PCCompositeType *type)
1180: {
1181: PetscFunctionBegin;
1183: PetscAssertPointer(type, 2);
1184: PetscUseMethod(pc, "PCASMGetLocalType_C", (PC, PCCompositeType *), (pc, type));
1185: PetscFunctionReturn(PETSC_SUCCESS);
1186: }
1188: /*@
1189: PCASMSetSortIndices - Determines whether subdomain indices are sorted.
1191: Logically Collective
1193: Input Parameters:
1194: + pc - the preconditioner context
1195: - doSort - sort the subdomain indices
1197: Level: intermediate
1199: .seealso: [](ch_ksp), `PCASM`, `PCASMSetLocalSubdomains()`, `PCASMSetTotalSubdomains()`, `PCASMGetSubKSP()`,
1200: `PCASMCreateSubdomains2D()`
1201: @*/
1202: PetscErrorCode PCASMSetSortIndices(PC pc, PetscBool doSort)
1203: {
1204: PetscFunctionBegin;
1207: PetscTryMethod(pc, "PCASMSetSortIndices_C", (PC, PetscBool), (pc, doSort));
1208: PetscFunctionReturn(PETSC_SUCCESS);
1209: }
1211: /*@C
1212: PCASMGetSubKSP - Gets the local `KSP` contexts for all blocks on
1213: this processor.
1215: Collective iff first_local is requested
1217: Input Parameter:
1218: . pc - the preconditioner context
1220: Output Parameters:
1221: + n_local - the number of blocks on this processor or `NULL`
1222: . first_local - the global number of the first block on this processor or `NULL`, all processors must request or all must pass `NULL`
1223: - ksp - the array of `KSP` contexts
1225: Level: advanced
1227: Notes:
1228: After `PCASMGetSubKSP()` the array of `KSP`s is not to be freed.
1230: You must call `KSPSetUp()` before calling `PCASMGetSubKSP()`.
1232: Fortran Note:
1233: Call `PCASMRestoreSubKSP()` when access to the array of `KSP` is no longer needed
1235: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`,
1236: `PCASMCreateSubdomains2D()`
1237: @*/
1238: PetscErrorCode PCASMGetSubKSP(PC pc, PetscInt *n_local, PetscInt *first_local, KSP *ksp[])
1239: {
1240: PetscFunctionBegin;
1242: PetscUseMethod(pc, "PCASMGetSubKSP_C", (PC, PetscInt *, PetscInt *, KSP **), (pc, n_local, first_local, ksp));
1243: PetscFunctionReturn(PETSC_SUCCESS);
1244: }
1246: /*MC
1247: PCASM - Use the (restricted) additive Schwarz method, each block is (approximately) solved with
1248: its own `KSP` object, {cite}`dryja1987additive` and {cite}`1sbg`
1250: Options Database Keys:
1251: + -pc_asm_blocks blks - Sets total blocks. Defaults to one block per MPI process.
1252: . -pc_asm_overlap ovl - Sets overlap
1253: . -pc_asm_type (basic|restrict|interpolate|none) - Sets `PCASMType`, default is restrict. See `PCASMSetType()`
1254: . -pc_asm_dm_subdomains (true|false) - use subdomains defined by the `DM` with `DMCreateDomainDecomposition()`
1255: - -pc_asm_local_type (additive|multiplicative) - Sets `PCCompositeType`, default is additive. See `PCASMSetLocalType()`
1257: Level: beginner
1259: Notes:
1260: If you run with, for example, 3 blocks on 1 processor or 3 blocks on 3 processors you
1261: will get a different convergence rate due to the default option of `-pc_asm_type restrict`. Use
1262: `-pc_asm_type basic` to get the same convergence behavior
1264: Each processor can have one or more blocks, but a block cannot be shared by more
1265: than one processor. Use `PCGASM` for subdomains shared by multiple processes.
1267: To set options on the solvers for each block append `-sub_` to all the `KSP`, and `PC`
1268: options database keys. For example, `-sub_pc_type ilu -sub_pc_factor_levels 1 -sub_ksp_type preonly`
1270: To set the options on the solvers separate for each block call `PCASMGetSubKSP()`
1271: and set the options directly on the resulting `KSP` object (you can access its `PC` with `KSPGetPC()`)
1273: If the `PC` has an associated `DM`, then, by default, `DMCreateDomainDecomposition()` is used to create the subdomains
1275: .seealso: [](ch_ksp), `PCCreate()`, `PCSetType()`, `PCType`, `PC`, `PCASMType`, `PCCompositeType`,
1276: `PCBJACOBI`, `PCASMGetSubKSP()`, `PCASMSetLocalSubdomains()`, `PCASMGetType()`, `PCASMSetLocalType()`, `PCASMGetLocalType()`,
1277: `PCASMSetTotalSubdomains()`, `PCSetModifySubMatrices()`, `PCASMSetOverlap()`, `PCASMSetType()`
1278: M*/
1280: PETSC_EXTERN PetscErrorCode PCCreate_ASM(PC pc)
1281: {
1282: PC_ASM *osm;
1284: PetscFunctionBegin;
1285: PetscCall(PetscNew(&osm));
1287: osm->n = PETSC_DECIDE;
1288: osm->n_local = 0;
1289: osm->n_local_true = PETSC_DECIDE;
1290: osm->overlap = 1;
1291: osm->ksp = NULL;
1292: osm->restriction = NULL;
1293: osm->lprolongation = NULL;
1294: osm->lrestriction = NULL;
1295: osm->x = NULL;
1296: osm->y = NULL;
1297: osm->is = NULL;
1298: osm->is_local = NULL;
1299: osm->mat = NULL;
1300: osm->pmat = NULL;
1301: osm->type = PC_ASM_RESTRICT;
1302: osm->loctype = PC_COMPOSITE_ADDITIVE;
1303: osm->sort_indices = PETSC_TRUE;
1304: osm->dm_subdomains = PETSC_FALSE;
1305: osm->sub_mat_type = NULL;
1307: pc->data = (void *)osm;
1308: pc->ops->apply = PCApply_ASM;
1309: pc->ops->matapply = PCMatApply_ASM;
1310: pc->ops->applytranspose = PCApplyTranspose_ASM;
1311: pc->ops->matapplytranspose = PCMatApplyTranspose_ASM;
1312: pc->ops->setup = PCSetUp_ASM;
1313: pc->ops->reset = PCReset_ASM;
1314: pc->ops->destroy = PCDestroy_ASM;
1315: pc->ops->setfromoptions = PCSetFromOptions_ASM;
1316: pc->ops->setuponblocks = PCSetUpOnBlocks_ASM;
1317: pc->ops->view = PCView_ASM;
1318: pc->ops->applyrichardson = NULL;
1320: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetLocalSubdomains_C", PCASMSetLocalSubdomains_ASM));
1321: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetTotalSubdomains_C", PCASMSetTotalSubdomains_ASM));
1322: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetOverlap_C", PCASMSetOverlap_ASM));
1323: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetType_C", PCASMSetType_ASM));
1324: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetType_C", PCASMGetType_ASM));
1325: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetLocalType_C", PCASMSetLocalType_ASM));
1326: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetLocalType_C", PCASMGetLocalType_ASM));
1327: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetSortIndices_C", PCASMSetSortIndices_ASM));
1328: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetSubKSP_C", PCASMGetSubKSP_ASM));
1329: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMGetSubMatType_C", PCASMGetSubMatType_ASM));
1330: PetscCall(PetscObjectComposeFunction((PetscObject)pc, "PCASMSetSubMatType_C", PCASMSetSubMatType_ASM));
1331: PetscFunctionReturn(PETSC_SUCCESS);
1332: }
1334: /*@C
1335: PCASMCreateSubdomains - Creates the index sets for the overlapping Schwarz
1336: preconditioner, `PCASM`, for any problem on a general grid.
1338: Collective
1340: Input Parameters:
1341: + A - The global matrix operator
1342: - n - the number of local blocks
1344: Output Parameter:
1345: . outis - the array of index sets defining the subdomains
1347: Level: advanced
1349: Note:
1350: This generates nonoverlapping subdomains; the `PCASM` will generate the overlap
1351: from these if you use `PCASMSetLocalSubdomains()`
1353: .seealso: [](ch_ksp), `PCASM`, `PCASMSetLocalSubdomains()`, `PCASMDestroySubdomains()`
1354: @*/
1355: PetscErrorCode PCASMCreateSubdomains(Mat A, PetscInt n, IS *outis[])
1356: {
1357: MatPartitioning mpart;
1358: const char *prefix;
1359: PetscInt i, j, rstart, rend, bs;
1360: PetscBool hasop, isbaij = PETSC_FALSE, foundpart = PETSC_FALSE;
1361: Mat Ad = NULL, adj;
1362: IS ispart, isnumb, *is;
1364: PetscFunctionBegin;
1366: PetscAssertPointer(outis, 3);
1367: PetscCheck(n >= 1, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "number of local blocks must be > 0, n = %" PetscInt_FMT, n);
1369: /* Get prefix, row distribution, and block size */
1370: PetscCall(MatGetOptionsPrefix(A, &prefix));
1371: PetscCall(MatGetOwnershipRange(A, &rstart, &rend));
1372: PetscCall(MatGetBlockSize(A, &bs));
1373: PetscCheck(rstart / bs * bs == rstart && rend / bs * bs == rend, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "bad row distribution [%" PetscInt_FMT ",%" PetscInt_FMT ") for matrix block size %" PetscInt_FMT, rstart, rend, bs);
1375: /* Get diagonal block from matrix if possible */
1376: PetscCall(MatHasOperation(A, MATOP_GET_DIAGONAL_BLOCK, &hasop));
1377: if (hasop) PetscCall(MatGetDiagonalBlock(A, &Ad));
1378: if (Ad) {
1379: PetscCall(PetscObjectBaseTypeCompare((PetscObject)Ad, MATSEQBAIJ, &isbaij));
1380: if (!isbaij) PetscCall(PetscObjectBaseTypeCompare((PetscObject)Ad, MATSEQSBAIJ, &isbaij));
1381: }
1382: if (Ad && n > 1) {
1383: PetscBool match, done;
1384: /* Try to setup a good matrix partitioning if available */
1385: PetscCall(MatPartitioningCreate(PETSC_COMM_SELF, &mpart));
1386: PetscCall(PetscObjectSetOptionsPrefix((PetscObject)mpart, prefix));
1387: PetscCall(MatPartitioningSetFromOptions(mpart));
1388: PetscCall(PetscObjectTypeCompare((PetscObject)mpart, MATPARTITIONINGCURRENT, &match));
1389: if (!match) PetscCall(PetscObjectTypeCompare((PetscObject)mpart, MATPARTITIONINGSQUARE, &match));
1390: if (!match) { /* assume a "good" partitioner is available */
1391: PetscInt na;
1392: const PetscInt *ia, *ja;
1393: PetscCall(MatGetRowIJ(Ad, 0, PETSC_TRUE, isbaij, &na, &ia, &ja, &done));
1394: if (done) {
1395: /* Build adjacency matrix by hand. Unfortunately a call to
1396: MatConvert(Ad,MATMPIADJ,MAT_INITIAL_MATRIX,&adj) will
1397: remove the block-aij structure and we cannot expect
1398: MatPartitioning to split vertices as we need */
1399: PetscInt i, j, len, nnz, cnt, *iia = NULL, *jja = NULL;
1400: const PetscInt *row;
1401: nnz = 0;
1402: for (i = 0; i < na; i++) { /* count number of nonzeros */
1403: len = ia[i + 1] - ia[i];
1404: row = ja + ia[i];
1405: for (j = 0; j < len; j++) {
1406: if (row[j] == i) { /* don't count diagonal */
1407: len--;
1408: break;
1409: }
1410: }
1411: nnz += len;
1412: }
1413: PetscCall(PetscMalloc1(na + 1, &iia));
1414: PetscCall(PetscMalloc1(nnz, &jja));
1415: nnz = 0;
1416: iia[0] = 0;
1417: for (i = 0; i < na; i++) { /* fill adjacency */
1418: cnt = 0;
1419: len = ia[i + 1] - ia[i];
1420: row = ja + ia[i];
1421: for (j = 0; j < len; j++) {
1422: if (row[j] != i) { /* if not diagonal */
1423: jja[nnz + cnt++] = row[j];
1424: }
1425: }
1426: nnz += cnt;
1427: iia[i + 1] = nnz;
1428: }
1429: /* Partitioning of the adjacency matrix */
1430: PetscCall(MatCreateMPIAdj(PETSC_COMM_SELF, na, na, iia, jja, NULL, &adj));
1431: PetscCall(MatPartitioningSetAdjacency(mpart, adj));
1432: PetscCall(MatPartitioningSetNParts(mpart, n));
1433: PetscCall(MatPartitioningApply(mpart, &ispart));
1434: PetscCall(ISPartitioningToNumbering(ispart, &isnumb));
1435: PetscCall(MatDestroy(&adj));
1436: foundpart = PETSC_TRUE;
1437: }
1438: PetscCall(MatRestoreRowIJ(Ad, 0, PETSC_TRUE, isbaij, &na, &ia, &ja, &done));
1439: }
1440: PetscCall(MatPartitioningDestroy(&mpart));
1441: }
1443: PetscCall(PetscMalloc1(n, &is));
1444: *outis = is;
1446: if (!foundpart) {
1447: /* Partitioning by contiguous chunks of rows */
1449: PetscInt mbs = (rend - rstart) / bs;
1450: PetscInt start = rstart;
1451: for (i = 0; i < n; i++) {
1452: PetscInt count = (mbs / n + ((mbs % n) > i)) * bs;
1453: PetscCall(ISCreateStride(PETSC_COMM_SELF, count, start, 1, &is[i]));
1454: start += count;
1455: }
1457: } else {
1458: /* Partitioning by adjacency of diagonal block */
1460: const PetscInt *numbering;
1461: PetscInt *count, nidx, *indices, *newidx, start = 0;
1462: /* Get node count in each partition */
1463: PetscCall(PetscMalloc1(n, &count));
1464: PetscCall(ISPartitioningCount(ispart, n, count));
1465: if (isbaij && bs > 1) { /* adjust for the block-aij case */
1466: for (i = 0; i < n; i++) count[i] *= bs;
1467: }
1468: /* Build indices from node numbering */
1469: PetscCall(ISGetLocalSize(isnumb, &nidx));
1470: PetscCall(PetscMalloc1(nidx, &indices));
1471: for (i = 0; i < nidx; i++) indices[i] = i; /* needs to be initialized */
1472: PetscCall(ISGetIndices(isnumb, &numbering));
1473: PetscCall(PetscSortIntWithPermutation(nidx, numbering, indices));
1474: PetscCall(ISRestoreIndices(isnumb, &numbering));
1475: if (isbaij && bs > 1) { /* adjust for the block-aij case */
1476: PetscCall(PetscMalloc1(nidx * bs, &newidx));
1477: for (i = 0; i < nidx; i++) {
1478: for (j = 0; j < bs; j++) newidx[i * bs + j] = indices[i] * bs + j;
1479: }
1480: PetscCall(PetscFree(indices));
1481: nidx *= bs;
1482: indices = newidx;
1483: }
1484: /* Shift to get global indices */
1485: for (i = 0; i < nidx; i++) indices[i] += rstart;
1487: /* Build the index sets for each block */
1488: for (i = 0; i < n; i++) {
1489: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, count[i], &indices[start], PETSC_COPY_VALUES, &is[i]));
1490: PetscCall(ISSort(is[i]));
1491: start += count[i];
1492: }
1494: PetscCall(PetscFree(count));
1495: PetscCall(PetscFree(indices));
1496: PetscCall(ISDestroy(&isnumb));
1497: PetscCall(ISDestroy(&ispart));
1498: }
1499: PetscFunctionReturn(PETSC_SUCCESS);
1500: }
1502: /*@C
1503: PCASMDestroySubdomains - Destroys the index sets created with
1504: `PCASMCreateSubdomains()`. Should be called after setting subdomains with `PCASMSetLocalSubdomains()`.
1506: Collective
1508: Input Parameters:
1509: + n - the number of index sets
1510: . is - the array of index sets
1511: - is_local - the array of local index sets, can be `NULL`
1513: Level: advanced
1515: Developer Note:
1516: The `IS` arguments should be a *[]
1518: .seealso: [](ch_ksp), `PCASM`, `PCASMCreateSubdomains()`, `PCASMSetLocalSubdomains()`
1519: @*/
1520: PetscErrorCode PCASMDestroySubdomains(PetscInt n, IS *is[], IS *is_local[])
1521: {
1522: PetscInt i;
1524: PetscFunctionBegin;
1525: if (n <= 0) PetscFunctionReturn(PETSC_SUCCESS);
1526: if (*is) {
1527: PetscAssertPointer(*is, 2);
1528: for (i = 0; i < n; i++) PetscCall(ISDestroy(&(*is)[i]));
1529: PetscCall(PetscFree(*is));
1530: }
1531: if (is_local && *is_local) {
1532: PetscAssertPointer(*is_local, 3);
1533: for (i = 0; i < n; i++) PetscCall(ISDestroy(&(*is_local)[i]));
1534: PetscCall(PetscFree(*is_local));
1535: }
1536: PetscFunctionReturn(PETSC_SUCCESS);
1537: }
1539: /*@C
1540: PCASMCreateSubdomains2D - Creates the index sets for the overlapping Schwarz
1541: preconditioner, `PCASM`, for a two-dimensional problem on a regular grid.
1543: Not Collective
1545: Input Parameters:
1546: + m - the number of mesh points in the x direction
1547: . n - the number of mesh points in the y direction
1548: . M - the number of subdomains in the x direction
1549: . N - the number of subdomains in the y direction
1550: . dof - degrees of freedom per node
1551: - overlap - overlap in mesh lines
1553: Output Parameters:
1554: + Nsub - the number of subdomains created
1555: . is - array of index sets defining overlapping (if overlap > 0) subdomains
1556: - is_local - array of index sets defining non-overlapping subdomains
1558: Level: advanced
1560: Note:
1561: Presently `PCAMSCreateSubdomains2d()` is valid only for sequential
1562: preconditioners. More general related routines are
1563: `PCASMSetTotalSubdomains()` and `PCASMSetLocalSubdomains()`.
1565: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetLocalSubdomains()`, `PCASMGetSubKSP()`,
1566: `PCASMSetOverlap()`
1567: @*/
1568: PetscErrorCode PCASMCreateSubdomains2D(PetscInt m, PetscInt n, PetscInt M, PetscInt N, PetscInt dof, PetscInt overlap, PetscInt *Nsub, IS *is[], IS *is_local[])
1569: {
1570: PetscInt i, j, height, width, ystart, xstart, yleft, yright, xleft, xright, loc_outer;
1571: PetscInt nidx, *idx, loc, ii, jj, count;
1573: PetscFunctionBegin;
1574: PetscCheck(dof == 1, PETSC_COMM_SELF, PETSC_ERR_SUP, "dof must be 1");
1576: *Nsub = N * M;
1577: PetscCall(PetscMalloc1(*Nsub, is));
1578: PetscCall(PetscMalloc1(*Nsub, is_local));
1579: ystart = 0;
1580: loc_outer = 0;
1581: for (i = 0; i < N; i++) {
1582: height = n / N + ((n % N) > i); /* height of subdomain */
1583: PetscCheck(height >= 2, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Too many N subdomains for mesh dimension n");
1584: yleft = ystart - overlap;
1585: if (yleft < 0) yleft = 0;
1586: yright = ystart + height + overlap;
1587: if (yright > n) yright = n;
1588: xstart = 0;
1589: for (j = 0; j < M; j++) {
1590: width = m / M + ((m % M) > j); /* width of subdomain */
1591: PetscCheck(width >= 2, PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Too many M subdomains for mesh dimension m");
1592: xleft = xstart - overlap;
1593: if (xleft < 0) xleft = 0;
1594: xright = xstart + width + overlap;
1595: if (xright > m) xright = m;
1596: nidx = (xright - xleft) * (yright - yleft);
1597: PetscCall(PetscMalloc1(nidx, &idx));
1598: loc = 0;
1599: for (ii = yleft; ii < yright; ii++) {
1600: count = m * ii + xleft;
1601: for (jj = xleft; jj < xright; jj++) idx[loc++] = count++;
1602: }
1603: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nidx, idx, PETSC_COPY_VALUES, (*is) + loc_outer));
1604: if (overlap == 0) {
1605: PetscCall(PetscObjectReference((PetscObject)(*is)[loc_outer]));
1607: (*is_local)[loc_outer] = (*is)[loc_outer];
1608: } else {
1609: for (loc = 0, ii = ystart; ii < ystart + height; ii++) {
1610: for (jj = xstart; jj < xstart + width; jj++) idx[loc++] = m * ii + jj;
1611: }
1612: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, loc, idx, PETSC_COPY_VALUES, *is_local + loc_outer));
1613: }
1614: PetscCall(PetscFree(idx));
1615: xstart += width;
1616: loc_outer++;
1617: }
1618: ystart += height;
1619: }
1620: for (i = 0; i < *Nsub; i++) PetscCall(ISSort((*is)[i]));
1621: PetscFunctionReturn(PETSC_SUCCESS);
1622: }
1624: /*@C
1625: PCASMGetLocalSubdomains - Gets the local subdomains (for this processor
1626: only) for the additive Schwarz preconditioner, `PCASM`.
1628: Not Collective
1630: Input Parameter:
1631: . pc - the preconditioner context
1633: Output Parameters:
1634: + n - if requested, the number of subdomains for this processor (default value = 1)
1635: . is - if requested, the index sets that define the subdomains for this processor
1636: - is_local - if requested, the index sets that define the local part of the subdomains for this processor (can be `NULL`)
1638: Level: advanced
1640: Note:
1641: The `IS` numbering is in the parallel, global numbering of the vector.
1643: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`, `PCASMGetSubKSP()`,
1644: `PCASMCreateSubdomains2D()`, `PCASMSetLocalSubdomains()`, `PCASMGetLocalSubmatrices()`
1645: @*/
1646: PetscErrorCode PCASMGetLocalSubdomains(PC pc, PetscInt *n, IS *is[], IS *is_local[])
1647: {
1648: PC_ASM *osm = (PC_ASM *)pc->data;
1649: PetscBool match;
1651: PetscFunctionBegin;
1653: if (n) PetscAssertPointer(n, 2);
1654: if (is) PetscAssertPointer(is, 3);
1655: if (is_local) PetscAssertPointer(is_local, 4);
1656: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCASM, &match));
1657: PetscCheck(match, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONG, "PC is not a PCASM");
1658: if (n) *n = osm->n_local_true;
1659: if (is) *is = osm->is;
1660: if (is_local) *is_local = osm->is_local;
1661: PetscFunctionReturn(PETSC_SUCCESS);
1662: }
1664: /*@C
1665: PCASMGetLocalSubmatrices - Gets the local submatrices (for this processor
1666: only) for the additive Schwarz preconditioner, `PCASM`.
1668: Not Collective
1670: Input Parameter:
1671: . pc - the preconditioner context
1673: Output Parameters:
1674: + n - if requested, the number of matrices for this processor (default value = 1)
1675: - mat - if requested, the matrices
1677: Level: advanced
1679: Notes:
1680: Call after `PCSetUp()` (or `KSPSetUp()`) but before `PCApply()` and before `PCSetUpOnBlocks()`)
1682: Usually one would use `PCSetModifySubMatrices()` to change the submatrices in building the preconditioner.
1684: .seealso: [](ch_ksp), `PCASM`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`, `PCASMGetSubKSP()`,
1685: `PCASMCreateSubdomains2D()`, `PCASMSetLocalSubdomains()`, `PCASMGetLocalSubdomains()`, `PCSetModifySubMatrices()`
1686: @*/
1687: PetscErrorCode PCASMGetLocalSubmatrices(PC pc, PetscInt *n, Mat *mat[])
1688: {
1689: PC_ASM *osm;
1690: PetscBool match;
1692: PetscFunctionBegin;
1694: if (n) PetscAssertPointer(n, 2);
1695: if (mat) PetscAssertPointer(mat, 3);
1696: PetscCheck(pc->setupcalled, PetscObjectComm((PetscObject)pc), PETSC_ERR_ARG_WRONGSTATE, "Must call after KSPSetUp() or PCSetUp().");
1697: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCASM, &match));
1698: if (!match) {
1699: if (n) *n = 0;
1700: if (mat) *mat = NULL;
1701: } else {
1702: osm = (PC_ASM *)pc->data;
1703: if (n) *n = osm->n_local_true;
1704: if (mat) *mat = osm->pmat;
1705: }
1706: PetscFunctionReturn(PETSC_SUCCESS);
1707: }
1709: /*@
1710: PCASMSetDMSubdomains - Indicates whether to use `DMCreateDomainDecomposition()` to define the subdomains, whenever possible.
1712: Logically Collective
1714: Input Parameters:
1715: + pc - the preconditioner
1716: - flg - boolean indicating whether to use subdomains defined by the `DM`
1718: Options Database Key:
1719: . -pc_asm_dm_subdomains (true|false) - use subdomains defined by the `DM` with `DMCreateDomainDecomposition()`
1721: Level: intermediate
1723: Note:
1724: `PCASMSetTotalSubdomains()` and `PCASMSetOverlap()` take precedence over `PCASMSetDMSubdomains()`,
1725: so setting either of the first two effectively turns the latter off.
1727: Developer Note:
1728: This should be `PCASMSetUseDMSubdomains()`, similarly for the options database key
1730: .seealso: [](ch_ksp), `PCASM`, `PCASMGetDMSubdomains()`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`,
1731: `PCASMCreateSubdomains2D()`, `PCASMSetLocalSubdomains()`, `PCASMGetLocalSubdomains()`
1732: @*/
1733: PetscErrorCode PCASMSetDMSubdomains(PC pc, PetscBool flg)
1734: {
1735: PC_ASM *osm = (PC_ASM *)pc->data;
1736: PetscBool match;
1738: PetscFunctionBegin;
1741: PetscCheck(!pc->setupcalled, ((PetscObject)pc)->comm, PETSC_ERR_ARG_WRONGSTATE, "Not for a setup PC.");
1742: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCASM, &match));
1743: if (match) osm->dm_subdomains = flg;
1744: PetscFunctionReturn(PETSC_SUCCESS);
1745: }
1747: /*@
1748: PCASMGetDMSubdomains - Returns flag indicating whether to use `DMCreateDomainDecomposition()` to define the subdomains, whenever possible.
1750: Not Collective
1752: Input Parameter:
1753: . pc - the preconditioner
1755: Output Parameter:
1756: . flg - boolean indicating whether to use subdomains defined by the `DM`
1758: Level: intermediate
1760: Developer Note:
1761: This should be `PCASMSetUseDMSubdomains()`
1763: .seealso: [](ch_ksp), `PCASM`, `PCASMSetDMSubdomains()`, `PCASMSetTotalSubdomains()`, `PCASMSetOverlap()`,
1764: `PCASMCreateSubdomains2D()`, `PCASMSetLocalSubdomains()`, `PCASMGetLocalSubdomains()`
1765: @*/
1766: PetscErrorCode PCASMGetDMSubdomains(PC pc, PetscBool *flg)
1767: {
1768: PC_ASM *osm = (PC_ASM *)pc->data;
1769: PetscBool match;
1771: PetscFunctionBegin;
1773: PetscAssertPointer(flg, 2);
1774: PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCASM, &match));
1775: if (match) *flg = osm->dm_subdomains;
1776: else *flg = PETSC_FALSE;
1777: PetscFunctionReturn(PETSC_SUCCESS);
1778: }
1780: /*@
1781: PCASMGetSubMatType - Gets the matrix type used for `PCASM` subsolves, as a string.
1783: Not Collective
1785: Input Parameter:
1786: . pc - the `PC`
1788: Output Parameter:
1789: . sub_mat_type - name of matrix type
1791: Level: advanced
1793: .seealso: [](ch_ksp), `PCASM`, `PCASMSetSubMatType()`, `PCSetType()`, `VecSetType()`, `MatType`, `Mat`
1794: @*/
1795: PetscErrorCode PCASMGetSubMatType(PC pc, MatType *sub_mat_type)
1796: {
1797: PetscFunctionBegin;
1799: PetscTryMethod(pc, "PCASMGetSubMatType_C", (PC, MatType *), (pc, sub_mat_type));
1800: PetscFunctionReturn(PETSC_SUCCESS);
1801: }
1803: /*@
1804: PCASMSetSubMatType - Set the type of matrix used for `PCASM` subsolves
1806: Collective
1808: Input Parameters:
1809: + pc - the `PC` object
1810: - sub_mat_type - the `MatType`
1812: Options Database Key:
1813: . -pc_asm_sub_mat_type sub_mat_type - Sets the matrix type used for subsolves, for example, seqaijviennacl.
1814: If you specify a base name like aijviennacl, the corresponding sequential type is assumed.
1816: Note:
1817: See `MatType` for available types
1819: Level: advanced
1821: .seealso: [](ch_ksp), `PCASM`, `PCASMGetSubMatType()`, `PCSetType()`, `VecSetType()`, `MatType`, `Mat`
1822: @*/
1823: PetscErrorCode PCASMSetSubMatType(PC pc, MatType sub_mat_type)
1824: {
1825: PetscFunctionBegin;
1827: PetscTryMethod(pc, "PCASMSetSubMatType_C", (PC, MatType), (pc, sub_mat_type));
1828: PetscFunctionReturn(PETSC_SUCCESS);
1829: }