Actual source code: gamg.c
petsc-3.7.5 2017-01-01
1: /*
2: GAMG geometric-algebric multigrid PC - Mark Adams 2011
3: */
4: #include <petsc/private/matimpl.h>
5: #include <../src/ksp/pc/impls/gamg/gamg.h> /*I "petscpc.h" I*/
6: #include <petsc/private/kspimpl.h>
7: #include <../src/ksp/pc/impls/bjacobi/bjacobi.h> /* Hack to access same_local_solves */
9: #if defined PETSC_GAMG_USE_LOG
10: PetscLogEvent petsc_gamg_setup_events[NUM_SET];
11: #endif
13: #if defined PETSC_USE_LOG
14: PetscLogEvent PC_GAMGGraph_AGG;
15: PetscLogEvent PC_GAMGGraph_GEO;
16: PetscLogEvent PC_GAMGCoarsen_AGG;
17: PetscLogEvent PC_GAMGCoarsen_GEO;
18: PetscLogEvent PC_GAMGProlongator_AGG;
19: PetscLogEvent PC_GAMGProlongator_GEO;
20: PetscLogEvent PC_GAMGOptProlongator_AGG;
21: #endif
23: #define GAMG_MAXLEVELS 30
25: /* #define GAMG_STAGES */
26: #if (defined PETSC_GAMG_USE_LOG && defined GAMG_STAGES)
27: static PetscLogStage gamg_stages[GAMG_MAXLEVELS];
28: #endif
30: static PetscFunctionList GAMGList = 0;
31: static PetscBool PCGAMGPackageInitialized;
33: /* ----------------------------------------------------------------------------- */
36: PetscErrorCode PCReset_GAMG(PC pc)
37: {
39: PC_MG *mg = (PC_MG*)pc->data;
40: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
43: if (pc_gamg->data) { /* this should not happen, cleaned up in SetUp */
44: PetscPrintf(PetscObjectComm((PetscObject)pc),"***[%d]%s this should not happen, cleaned up in SetUp\n",0,__FUNCT__);
45: PetscFree(pc_gamg->data);
46: }
47: pc_gamg->data_sz = 0;
48: PetscFree(pc_gamg->orig_data);
49: return(0);
50: }
52: /* -------------------------------------------------------------------------- */
53: /*
54: PCGAMGCreateLevel_GAMG: create coarse op with RAP. repartition and/or reduce number
55: of active processors.
57: Input Parameter:
58: . pc - parameters + side effect: coarse data in 'pc_gamg->data' and
59: 'pc_gamg->data_sz' are changed via repartitioning/reduction.
60: . Amat_fine - matrix on this fine (k) level
61: . cr_bs - coarse block size
62: In/Output Parameter:
63: . a_P_inout - prolongation operator to the next level (k-->k-1)
64: . a_nactive_proc - number of active procs
65: Output Parameter:
66: . a_Amat_crs - coarse matrix that is created (k-1)
67: */
71: static PetscErrorCode PCGAMGCreateLevel_GAMG(PC pc,Mat Amat_fine,PetscInt cr_bs,
72: Mat *a_P_inout,Mat *a_Amat_crs,PetscMPIInt *a_nactive_proc,
73: IS * Pcolumnperm)
74: {
75: PetscErrorCode ierr;
76: PC_MG *mg = (PC_MG*)pc->data;
77: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
78: Mat Cmat,Pold=*a_P_inout;
79: MPI_Comm comm;
80: PetscMPIInt rank,size,new_size,nactive=*a_nactive_proc;
81: PetscInt ncrs_eq,ncrs,f_bs;
84: PetscObjectGetComm((PetscObject)Amat_fine,&comm);
85: MPI_Comm_rank(comm, &rank);
86: MPI_Comm_size(comm, &size);
87: MatGetBlockSize(Amat_fine, &f_bs);
88: MatPtAP(Amat_fine, Pold, MAT_INITIAL_MATRIX, 2.0, &Cmat);
90: /* set 'ncrs' (nodes), 'ncrs_eq' (equations)*/
91: MatGetLocalSize(Cmat, &ncrs_eq, NULL);
92: if (pc_gamg->data_cell_rows>0) {
93: ncrs = pc_gamg->data_sz/pc_gamg->data_cell_cols/pc_gamg->data_cell_rows;
94: } else {
95: PetscInt bs;
96: MatGetBlockSize(Cmat, &bs);
97: ncrs = ncrs_eq/bs;
98: }
100: /* get number of PEs to make active 'new_size', reduce, can be any integer 1-P */
101: {
102: PetscInt ncrs_eq_glob;
103: MatGetSize(Cmat, &ncrs_eq_glob, NULL);
104: new_size = (PetscMPIInt)((float)ncrs_eq_glob/(float)pc_gamg->min_eq_proc + 0.5); /* hardwire min. number of eq/proc */
105: if (!new_size) new_size = 1; /* not likely, posible? */
106: else if (new_size >= nactive) new_size = nactive; /* no change, rare */
107: }
109: if (Pcolumnperm) *Pcolumnperm = NULL;
111: if (!pc_gamg->repart && new_size==nactive) *a_Amat_crs = Cmat; /* output - no repartitioning or reduction - could bail here */
112: else {
113: PetscInt *counts,*newproc_idx,ii,jj,kk,strideNew,*tidx,ncrs_new,ncrs_eq_new,nloc_old;
114: IS is_eq_newproc,is_eq_num,is_eq_num_prim,new_eq_indices;
116: nloc_old = ncrs_eq/cr_bs;
117: if (ncrs_eq % cr_bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"ncrs_eq %D not divisible by cr_bs %D",ncrs_eq,cr_bs);
118: #if defined PETSC_GAMG_USE_LOG
119: PetscLogEventBegin(petsc_gamg_setup_events[SET12],0,0,0,0);
120: #endif
121: /* make 'is_eq_newproc' */
122: PetscMalloc1(size, &counts);
123: if (pc_gamg->repart) {
124: /* Repartition Cmat_{k} and move colums of P^{k}_{k-1} and coordinates of primal part accordingly */
125: Mat adj;
127: PetscInfo3(pc,"Repartition: size (active): %D --> %D, neq = %D\n",*a_nactive_proc,new_size,ncrs_eq);
129: /* get 'adj' */
130: if (cr_bs == 1) {
131: MatConvert(Cmat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj);
132: } else {
133: /* make a scalar matrix to partition (no Stokes here) */
134: Mat tMat;
135: PetscInt Istart_crs,Iend_crs,ncols,jj,Ii;
136: const PetscScalar *vals;
137: const PetscInt *idx;
138: PetscInt *d_nnz, *o_nnz, M, N;
139: static PetscInt llev = 0;
140: MatType mtype;
142: PetscMalloc2(ncrs, &d_nnz,ncrs, &o_nnz);
143: MatGetOwnershipRange(Cmat, &Istart_crs, &Iend_crs);
144: MatGetSize(Cmat, &M, &N);
145: for (Ii = Istart_crs, jj = 0; Ii < Iend_crs; Ii += cr_bs, jj++) {
146: MatGetRow(Cmat,Ii,&ncols,0,0);
147: d_nnz[jj] = ncols/cr_bs;
148: o_nnz[jj] = ncols/cr_bs;
149: MatRestoreRow(Cmat,Ii,&ncols,0,0);
150: if (d_nnz[jj] > ncrs) d_nnz[jj] = ncrs;
151: if (o_nnz[jj] > (M/cr_bs-ncrs)) o_nnz[jj] = M/cr_bs-ncrs;
152: }
154: MatGetType(Amat_fine,&mtype);
155: MatCreate(comm, &tMat);
156: MatSetSizes(tMat, ncrs, ncrs,PETSC_DETERMINE, PETSC_DETERMINE);
157: MatSetType(tMat,mtype);
158: MatSeqAIJSetPreallocation(tMat,0,d_nnz);
159: MatMPIAIJSetPreallocation(tMat,0,d_nnz,0,o_nnz);
160: PetscFree2(d_nnz,o_nnz);
162: for (ii = Istart_crs; ii < Iend_crs; ii++) {
163: PetscInt dest_row = ii/cr_bs;
164: MatGetRow(Cmat,ii,&ncols,&idx,&vals);
165: for (jj = 0; jj < ncols; jj++) {
166: PetscInt dest_col = idx[jj]/cr_bs;
167: PetscScalar v = 1.0;
168: MatSetValues(tMat,1,&dest_row,1,&dest_col,&v,ADD_VALUES);
169: }
170: MatRestoreRow(Cmat,ii,&ncols,&idx,&vals);
171: }
172: MatAssemblyBegin(tMat,MAT_FINAL_ASSEMBLY);
173: MatAssemblyEnd(tMat,MAT_FINAL_ASSEMBLY);
175: if (llev++ == -1) {
176: PetscViewer viewer; char fname[32];
177: PetscSNPrintf(fname,sizeof(fname),"part_mat_%D.mat",llev);
178: PetscViewerBinaryOpen(comm,fname,FILE_MODE_WRITE,&viewer);
179: MatView(tMat, viewer);
180: PetscViewerDestroy(&viewer);
181: }
183: MatConvert(tMat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj);
185: MatDestroy(&tMat);
186: } /* create 'adj' */
188: { /* partition: get newproc_idx */
189: char prefix[256];
190: const char *pcpre;
191: const PetscInt *is_idx;
192: MatPartitioning mpart;
193: IS proc_is;
194: PetscInt targetPE;
196: MatPartitioningCreate(comm, &mpart);
197: MatPartitioningSetAdjacency(mpart, adj);
198: PCGetOptionsPrefix(pc, &pcpre);
199: PetscSNPrintf(prefix,sizeof(prefix),"%spc_gamg_",pcpre ? pcpre : "");
200: PetscObjectSetOptionsPrefix((PetscObject)mpart,prefix);
201: MatPartitioningSetFromOptions(mpart);
202: MatPartitioningSetNParts(mpart, new_size);
203: MatPartitioningApply(mpart, &proc_is);
204: MatPartitioningDestroy(&mpart);
206: /* collect IS info */
207: PetscMalloc1(ncrs_eq, &newproc_idx);
208: ISGetIndices(proc_is, &is_idx);
209: targetPE = 1; /* bring to "front" of machine */
210: /*targetPE = size/new_size;*/ /* spread partitioning across machine */
211: for (kk = jj = 0 ; kk < nloc_old ; kk++) {
212: for (ii = 0 ; ii < cr_bs ; ii++, jj++) {
213: newproc_idx[jj] = is_idx[kk] * targetPE; /* distribution */
214: }
215: }
216: ISRestoreIndices(proc_is, &is_idx);
217: ISDestroy(&proc_is);
218: }
219: MatDestroy(&adj);
221: ISCreateGeneral(comm, ncrs_eq, newproc_idx, PETSC_COPY_VALUES, &is_eq_newproc);
222: PetscFree(newproc_idx);
223: } else { /* simple aggreagtion of parts -- 'is_eq_newproc' */
225: PetscInt rfactor,targetPE;
226: /* find factor */
227: if (new_size == 1) rfactor = size; /* easy */
228: else {
229: PetscReal best_fact = 0.;
230: jj = -1;
231: for (kk = 1 ; kk <= size ; kk++) {
232: if (!(size%kk)) { /* a candidate */
233: PetscReal nactpe = (PetscReal)size/(PetscReal)kk, fact = nactpe/(PetscReal)new_size;
234: if (fact > 1.0) fact = 1./fact; /* keep fact < 1 */
235: if (fact > best_fact) {
236: best_fact = fact; jj = kk;
237: }
238: }
239: }
240: if (jj != -1) rfactor = jj;
241: else rfactor = 1; /* does this happen .. a prime */
242: }
243: new_size = size/rfactor;
245: if (new_size==nactive) {
246: *a_Amat_crs = Cmat; /* output - no repartitioning or reduction, bail out because nested here */
247: PetscFree(counts);
248: PetscInfo2(pc,"Aggregate processors noop: new_size=%D, neq(loc)=%D\n",new_size,ncrs_eq);
249: #if defined PETSC_GAMG_USE_LOG
250: PetscLogEventEnd(petsc_gamg_setup_events[SET12],0,0,0,0);
251: #endif
252: return(0);
253: }
255: PetscInfo1(pc,"Number of equations (loc) %D with simple aggregation\n",ncrs_eq);
256: targetPE = rank/rfactor;
257: ISCreateStride(comm, ncrs_eq, targetPE, 0, &is_eq_newproc);
258: } /* end simple 'is_eq_newproc' */
260: /*
261: Create an index set from the is_eq_newproc index set to indicate the mapping TO
262: */
263: ISPartitioningToNumbering(is_eq_newproc, &is_eq_num);
264: is_eq_num_prim = is_eq_num;
265: /*
266: Determine how many equations/vertices are assigned to each processor
267: */
268: ISPartitioningCount(is_eq_newproc, size, counts);
269: ncrs_eq_new = counts[rank];
270: ISDestroy(&is_eq_newproc);
271: ncrs_new = ncrs_eq_new/cr_bs; /* eqs */
273: PetscFree(counts);
274: #if defined PETSC_GAMG_USE_LOG
275: PetscLogEventEnd(petsc_gamg_setup_events[SET12],0,0,0,0);
276: #endif
277: /* data movement scope -- this could be moved to subclasses so that we don't try to cram all auxilary data into some complex abstracted thing */
278: {
279: Vec src_crd, dest_crd;
280: const PetscInt *idx,ndata_rows=pc_gamg->data_cell_rows,ndata_cols=pc_gamg->data_cell_cols,node_data_sz=ndata_rows*ndata_cols;
281: VecScatter vecscat;
282: PetscScalar *array;
283: IS isscat;
285: /* move data (for primal equations only) */
286: /* Create a vector to contain the newly ordered element information */
287: VecCreate(comm, &dest_crd);
288: VecSetSizes(dest_crd, node_data_sz*ncrs_new, PETSC_DECIDE);
289: VecSetType(dest_crd,VECSTANDARD); /* this is needed! */
290: /*
291: There are 'ndata_rows*ndata_cols' data items per node, (one can think of the vectors of having
292: a block size of ...). Note, ISs are expanded into equation space by 'cr_bs'.
293: */
294: PetscMalloc1(ncrs*node_data_sz, &tidx);
295: ISGetIndices(is_eq_num_prim, &idx);
296: for (ii=0,jj=0; ii<ncrs; ii++) {
297: PetscInt id = idx[ii*cr_bs]/cr_bs; /* get node back */
298: for (kk=0; kk<node_data_sz; kk++, jj++) tidx[jj] = id*node_data_sz + kk;
299: }
300: ISRestoreIndices(is_eq_num_prim, &idx);
301: ISCreateGeneral(comm, node_data_sz*ncrs, tidx, PETSC_COPY_VALUES, &isscat);
302: PetscFree(tidx);
303: /*
304: Create a vector to contain the original vertex information for each element
305: */
306: VecCreateSeq(PETSC_COMM_SELF, node_data_sz*ncrs, &src_crd);
307: for (jj=0; jj<ndata_cols; jj++) {
308: const PetscInt stride0=ncrs*pc_gamg->data_cell_rows;
309: for (ii=0; ii<ncrs; ii++) {
310: for (kk=0; kk<ndata_rows; kk++) {
311: PetscInt ix = ii*ndata_rows + kk + jj*stride0, jx = ii*node_data_sz + kk*ndata_cols + jj;
312: PetscScalar tt = (PetscScalar)pc_gamg->data[ix];
313: VecSetValues(src_crd, 1, &jx, &tt, INSERT_VALUES);
314: }
315: }
316: }
317: VecAssemblyBegin(src_crd);
318: VecAssemblyEnd(src_crd);
319: /*
320: Scatter the element vertex information (still in the original vertex ordering)
321: to the correct processor
322: */
323: VecScatterCreate(src_crd, NULL, dest_crd, isscat, &vecscat);
324: ISDestroy(&isscat);
325: VecScatterBegin(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);
326: VecScatterEnd(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);
327: VecScatterDestroy(&vecscat);
328: VecDestroy(&src_crd);
329: /*
330: Put the element vertex data into a new allocation of the gdata->ele
331: */
332: PetscFree(pc_gamg->data);
333: PetscMalloc1(node_data_sz*ncrs_new, &pc_gamg->data);
335: pc_gamg->data_sz = node_data_sz*ncrs_new;
336: strideNew = ncrs_new*ndata_rows;
338: VecGetArray(dest_crd, &array);
339: for (jj=0; jj<ndata_cols; jj++) {
340: for (ii=0; ii<ncrs_new; ii++) {
341: for (kk=0; kk<ndata_rows; kk++) {
342: PetscInt ix = ii*ndata_rows + kk + jj*strideNew, jx = ii*node_data_sz + kk*ndata_cols + jj;
343: pc_gamg->data[ix] = PetscRealPart(array[jx]);
344: }
345: }
346: }
347: VecRestoreArray(dest_crd, &array);
348: VecDestroy(&dest_crd);
349: }
350: /* move A and P (columns) with new layout */
351: #if defined PETSC_GAMG_USE_LOG
352: PetscLogEventBegin(petsc_gamg_setup_events[SET13],0,0,0,0);
353: #endif
355: /*
356: Invert for MatGetSubMatrix
357: */
358: ISInvertPermutation(is_eq_num, ncrs_eq_new, &new_eq_indices);
359: ISSort(new_eq_indices); /* is this needed? */
360: ISSetBlockSize(new_eq_indices, cr_bs);
361: if (is_eq_num != is_eq_num_prim) {
362: ISDestroy(&is_eq_num_prim); /* could be same as 'is_eq_num' */
363: }
364: if (Pcolumnperm) {
365: PetscObjectReference((PetscObject)new_eq_indices);
366: *Pcolumnperm = new_eq_indices;
367: }
368: ISDestroy(&is_eq_num);
369: #if defined PETSC_GAMG_USE_LOG
370: PetscLogEventEnd(petsc_gamg_setup_events[SET13],0,0,0,0);
371: PetscLogEventBegin(petsc_gamg_setup_events[SET14],0,0,0,0);
372: #endif
373: /* 'a_Amat_crs' output */
374: {
375: Mat mat;
376: MatGetSubMatrix(Cmat, new_eq_indices, new_eq_indices, MAT_INITIAL_MATRIX, &mat);
377: *a_Amat_crs = mat;
379: if (!PETSC_TRUE) {
380: PetscInt cbs, rbs;
381: MatGetBlockSizes(Cmat, &rbs, &cbs);
382: PetscPrintf(MPI_COMM_SELF,"[%d]%s Old Mat rbs=%d cbs=%d\n",rank,__FUNCT__,rbs,cbs);
383: MatGetBlockSizes(mat, &rbs, &cbs);
384: PetscPrintf(MPI_COMM_SELF,"[%d]%s New Mat rbs=%d cbs=%d cr_bs=%d\n",rank,__FUNCT__,rbs,cbs,cr_bs);
385: }
386: }
387: MatDestroy(&Cmat);
389: #if defined PETSC_GAMG_USE_LOG
390: PetscLogEventEnd(petsc_gamg_setup_events[SET14],0,0,0,0);
391: #endif
392: /* prolongator */
393: {
394: IS findices;
395: PetscInt Istart,Iend;
396: Mat Pnew;
397: MatGetOwnershipRange(Pold, &Istart, &Iend);
398: #if defined PETSC_GAMG_USE_LOG
399: PetscLogEventBegin(petsc_gamg_setup_events[SET15],0,0,0,0);
400: #endif
401: ISCreateStride(comm,Iend-Istart,Istart,1,&findices);
402: ISSetBlockSize(findices,f_bs);
403: MatGetSubMatrix(Pold, findices, new_eq_indices, MAT_INITIAL_MATRIX, &Pnew);
404: ISDestroy(&findices);
406: if (!PETSC_TRUE) {
407: PetscInt cbs, rbs;
408: MatGetBlockSizes(Pold, &rbs, &cbs);
409: PetscPrintf(MPI_COMM_SELF,"[%d]%s Pold rbs=%d cbs=%d\n",rank,__FUNCT__,rbs,cbs);
410: MatGetBlockSizes(Pnew, &rbs, &cbs);
411: PetscPrintf(MPI_COMM_SELF,"[%d]%s Pnew rbs=%d cbs=%d\n",rank,__FUNCT__,rbs,cbs);
412: }
413: #if defined PETSC_GAMG_USE_LOG
414: PetscLogEventEnd(petsc_gamg_setup_events[SET15],0,0,0,0);
415: #endif
416: MatDestroy(a_P_inout);
418: /* output - repartitioned */
419: *a_P_inout = Pnew;
420: }
421: ISDestroy(&new_eq_indices);
423: *a_nactive_proc = new_size; /* output */
424: }
426: /* outout matrix data */
427: if (!PETSC_TRUE) {
428: PetscViewer viewer; char fname[32]; static int llev=0; Cmat = *a_Amat_crs;
429: if (!llev) {
430: sprintf(fname,"Cmat_%d.m",llev++);
431: PetscViewerASCIIOpen(comm,fname,&viewer);
432: PetscViewerPushFormat(viewer, PETSC_VIEWER_ASCII_MATLAB);
433: MatView(Amat_fine, viewer);
434: PetscViewerPopFormat(viewer);
435: PetscViewerDestroy(&viewer);
436: }
437: sprintf(fname,"Cmat_%d.m",llev++);
438: PetscViewerASCIIOpen(comm,fname,&viewer);
439: PetscViewerPushFormat(viewer, PETSC_VIEWER_ASCII_MATLAB);
440: MatView(Cmat, viewer);
441: PetscViewerPopFormat(viewer);
442: PetscViewerDestroy(&viewer);
443: }
444: return(0);
445: }
447: /* -------------------------------------------------------------------------- */
448: /*
449: PCSetUp_GAMG - Prepares for the use of the GAMG preconditioner
450: by setting data structures and options.
452: Input Parameter:
453: . pc - the preconditioner context
455: */
458: PetscErrorCode PCSetUp_GAMG(PC pc)
459: {
461: PC_MG *mg = (PC_MG*)pc->data;
462: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
463: Mat Pmat = pc->pmat;
464: PetscInt fine_level,level,level1,bs,M,qq,lidx,nASMBlocksArr[GAMG_MAXLEVELS];
465: MPI_Comm comm;
466: PetscMPIInt rank,size,nactivepe;
467: Mat Aarr[GAMG_MAXLEVELS],Parr[GAMG_MAXLEVELS];
468: IS *ASMLocalIDsArr[GAMG_MAXLEVELS];
469: PetscLogDouble nnz0=0.,nnztot=0.;
470: MatInfo info;
473: PetscObjectGetComm((PetscObject)pc,&comm);
474: MPI_Comm_rank(comm,&rank);
475: MPI_Comm_size(comm,&size);
477: if (pc_gamg->setup_count++ > 0) {
478: if ((PetscBool)(!pc_gamg->reuse_prol)) {
479: /* reset everything */
480: PCReset_MG(pc);
481: pc->setupcalled = 0;
482: } else {
483: PC_MG_Levels **mglevels = mg->levels;
484: /* just do Galerkin grids */
485: Mat B,dA,dB;
487: if (!pc->setupcalled) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"PCSetUp() has not been called yet");
488: if (pc_gamg->Nlevels > 1) {
489: /* currently only handle case where mat and pmat are the same on coarser levels */
490: KSPGetOperators(mglevels[pc_gamg->Nlevels-1]->smoothd,&dA,&dB);
491: /* (re)set to get dirty flag */
492: KSPSetOperators(mglevels[pc_gamg->Nlevels-1]->smoothd,dA,dB);
494: for (level=pc_gamg->Nlevels-2; level>=0; level--) {
495: /* the first time through the matrix structure has changed from repartitioning */
496: if (pc_gamg->setup_count==2) {
497: MatPtAP(dB,mglevels[level+1]->interpolate,MAT_INITIAL_MATRIX,1.0,&B);
498: MatDestroy(&mglevels[level]->A);
500: mglevels[level]->A = B;
501: } else {
502: KSPGetOperators(mglevels[level]->smoothd,NULL,&B);
503: MatPtAP(dB,mglevels[level+1]->interpolate,MAT_REUSE_MATRIX,1.0,&B);
504: }
505: KSPSetOperators(mglevels[level]->smoothd,B,B);
506: dB = B;
507: }
508: }
510: PCSetUp_MG(pc);
512: return(0);
513: }
514: }
516: if (!pc_gamg->data) {
517: if (pc_gamg->orig_data) {
518: MatGetBlockSize(Pmat, &bs);
519: MatGetLocalSize(Pmat, &qq, NULL);
521: pc_gamg->data_sz = (qq/bs)*pc_gamg->orig_data_cell_rows*pc_gamg->orig_data_cell_cols;
522: pc_gamg->data_cell_rows = pc_gamg->orig_data_cell_rows;
523: pc_gamg->data_cell_cols = pc_gamg->orig_data_cell_cols;
525: PetscMalloc1(pc_gamg->data_sz, &pc_gamg->data);
526: for (qq=0; qq<pc_gamg->data_sz; qq++) pc_gamg->data[qq] = pc_gamg->orig_data[qq];
527: } else {
528: if (!pc_gamg->ops->createdefaultdata) SETERRQ(comm,PETSC_ERR_PLIB,"'createdefaultdata' not set(?) need to support NULL data");
529: pc_gamg->ops->createdefaultdata(pc,Pmat);
530: }
531: }
533: /* cache original data for reuse */
534: if (!pc_gamg->orig_data && (PetscBool)(!pc_gamg->reuse_prol)) {
535: PetscMalloc1(pc_gamg->data_sz, &pc_gamg->orig_data);
536: for (qq=0; qq<pc_gamg->data_sz; qq++) pc_gamg->orig_data[qq] = pc_gamg->data[qq];
537: pc_gamg->orig_data_cell_rows = pc_gamg->data_cell_rows;
538: pc_gamg->orig_data_cell_cols = pc_gamg->data_cell_cols;
539: }
541: /* get basic dims */
542: MatGetBlockSize(Pmat, &bs);
543: MatGetSize(Pmat, &M, &qq);
545: MatGetInfo(Pmat,MAT_GLOBAL_SUM,&info); /* global reduction */
546: nnz0 = info.nz_used;
547: nnztot = info.nz_used;
548: PetscInfo6(pc,"level %d) N=%D, n data rows=%d, n data cols=%d, nnz/row (ave)=%d, np=%d\n",
549: 0,M,pc_gamg->data_cell_rows,pc_gamg->data_cell_cols,
550: (int)(nnz0/(PetscReal)M+0.5),size);
551:
553: /* Get A_i and R_i */
554: for (level=0, Aarr[0]=Pmat, nactivepe = size; /* hard wired stopping logic */
555: level < (pc_gamg->Nlevels-1) && (!level || M>pc_gamg->coarse_eq_limit);
556: level++) {
557: pc_gamg->current_level = level;
558: level1 = level + 1;
559: #if defined PETSC_GAMG_USE_LOG
560: PetscLogEventBegin(petsc_gamg_setup_events[SET1],0,0,0,0);
561: #if (defined GAMG_STAGES)
562: PetscLogStagePush(gamg_stages[level]);
563: #endif
564: #endif
565: { /* construct prolongator */
566: Mat Gmat;
567: PetscCoarsenData *agg_lists;
568: Mat Prol11;
570: pc_gamg->ops->graph(pc,Aarr[level], &Gmat);
571: pc_gamg->ops->coarsen(pc, &Gmat, &agg_lists);
572: pc_gamg->ops->prolongator(pc,Aarr[level],Gmat,agg_lists,&Prol11);
574: /* could have failed to create new level */
575: if (Prol11) {
576: /* get new block size of coarse matrices */
577: MatGetBlockSizes(Prol11, NULL, &bs);
579: if (pc_gamg->ops->optprolongator) {
580: /* smooth */
581: pc_gamg->ops->optprolongator(pc, Aarr[level], &Prol11);
582: }
584: Parr[level1] = Prol11;
585: } else Parr[level1] = NULL;
587: if (pc_gamg->use_aggs_in_gasm) {
588: PetscInt bs;
589: MatGetBlockSizes(Prol11, &bs, NULL);
590: PetscCDGetASMBlocks(agg_lists, bs, &nASMBlocksArr[level], &ASMLocalIDsArr[level]);
591: }
593: MatDestroy(&Gmat);
594: PetscCDDestroy(agg_lists);
595: } /* construct prolongator scope */
596: #if defined PETSC_GAMG_USE_LOG
597: PetscLogEventEnd(petsc_gamg_setup_events[SET1],0,0,0,0);
598: #endif
599: if (!level) Aarr[0] = Pmat; /* use Pmat for finest level setup */
600: if (!Parr[level1]) {
601: PetscInfo1(pc,"Stop gridding, level %D\n",level);
602: #if (defined PETSC_GAMG_USE_LOG && defined GAMG_STAGES)
603: PetscLogStagePop();
604: #endif
605: break;
606: }
607: #if defined PETSC_GAMG_USE_LOG
608: PetscLogEventBegin(petsc_gamg_setup_events[SET2],0,0,0,0);
609: #endif
611: pc_gamg->ops->createlevel(pc, Aarr[level], bs,&Parr[level1], &Aarr[level1], &nactivepe, NULL);
613: #if defined PETSC_GAMG_USE_LOG
614: PetscLogEventEnd(petsc_gamg_setup_events[SET2],0,0,0,0);
615: #endif
616: MatGetSize(Aarr[level1], &M, &qq);
618: MatGetInfo(Aarr[level1], MAT_GLOBAL_SUM, &info);
619: nnztot += info.nz_used;
620: PetscInfo5(pc,"%d) N=%D, n data cols=%d, nnz/row (ave)=%d, %d active pes\n",level1,M,pc_gamg->data_cell_cols,(int)(info.nz_used/(PetscReal)M),nactivepe);
622: #if (defined PETSC_GAMG_USE_LOG && defined GAMG_STAGES)
623: PetscLogStagePop();
624: #endif
625: /* stop if one node or one proc -- could pull back for singular problems */
626: if ( (pc_gamg->data_cell_cols && M/pc_gamg->data_cell_cols < 2) || (!pc_gamg->data_cell_cols && M/bs < 2) ) {
627: PetscInfo2(pc,"HARD stop of coarsening on level %D. Grid too small: %D block nodes\n",level,M/bs);
628: level++;
629: break;
630: }
631: } /* levels */
632: PetscFree(pc_gamg->data);
634: PetscInfo2(pc,"%D levels, grid complexity = %g\n",level+1,nnztot/nnz0);
635: pc_gamg->Nlevels = level + 1;
636: fine_level = level;
637: PCMGSetLevels(pc,pc_gamg->Nlevels,NULL);
639: /* simple setup */
640: if (!PETSC_TRUE) {
641: PC_MG_Levels **mglevels = mg->levels;
642: for (lidx=0,level=pc_gamg->Nlevels-1;
643: lidx<fine_level;
644: lidx++, level--) {
645: PCMGSetInterpolation(pc, lidx+1, Parr[level]);
646: KSPSetOperators(mglevels[lidx]->smoothd, Aarr[level], Aarr[level]);
647: MatDestroy(&Parr[level]);
648: MatDestroy(&Aarr[level]);
649: }
650: KSPSetOperators(mglevels[fine_level]->smoothd, Aarr[0], Aarr[0]);
652: PCSetUp_MG(pc);
653: } else if (pc_gamg->Nlevels > 1) { /* don't setup MG if one level */
654: /* set default smoothers & set operators */
655: for (lidx = 1, level = pc_gamg->Nlevels-2;
656: lidx <= fine_level;
657: lidx++, level--) {
658: KSP smoother;
659: PC subpc;
661: PCMGGetSmoother(pc, lidx, &smoother);
662: KSPGetPC(smoother, &subpc);
664: KSPSetNormType(smoother, KSP_NORM_NONE);
665: /* set ops */
666: KSPSetOperators(smoother, Aarr[level], Aarr[level]);
667: PCMGSetInterpolation(pc, lidx, Parr[level+1]);
669: /* set defaults */
670: KSPSetType(smoother, KSPCHEBYSHEV);
672: /* set blocks for GASM smoother that uses the 'aggregates' */
673: if (pc_gamg->use_aggs_in_gasm) {
674: PetscInt sz;
675: IS *is;
677: sz = nASMBlocksArr[level];
678: is = ASMLocalIDsArr[level];
679: PCSetType(subpc, PCGASM);
680: PCGASMSetOverlap(subpc, 0);
681: if (!sz) {
682: IS is;
683: PetscInt my0,kk;
684: MatGetOwnershipRange(Aarr[level], &my0, &kk);
685: ISCreateGeneral(PETSC_COMM_SELF, 1, &my0, PETSC_COPY_VALUES, &is);
686: PCGASMSetSubdomains(subpc, 1, &is, NULL);
687: ISDestroy(&is);
688: } else {
689: PetscInt kk;
690: PCGASMSetSubdomains(subpc, sz, is, NULL);
691: for (kk=0; kk<sz; kk++) {
692: ISDestroy(&is[kk]);
693: }
694: PetscFree(is);
695: }
696: ASMLocalIDsArr[level] = NULL;
697: nASMBlocksArr[level] = 0;
698: PCGASMSetType(subpc, PC_GASM_BASIC);
699: } else {
700: PCSetType(subpc, PCSOR);
701: }
702: }
703: {
704: /* coarse grid */
705: KSP smoother,*k2; PC subpc,pc2; PetscInt ii,first;
706: Mat Lmat = Aarr[(level=pc_gamg->Nlevels-1)]; lidx = 0;
707: PCMGGetSmoother(pc, lidx, &smoother);
708: KSPSetOperators(smoother, Lmat, Lmat);
709: KSPSetNormType(smoother, KSP_NORM_NONE);
710: KSPGetPC(smoother, &subpc);
711: PCSetType(subpc, PCBJACOBI);
712: PCSetUp(subpc);
713: PCBJacobiGetSubKSP(subpc,&ii,&first,&k2);
714: if (ii != 1) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_PLIB,"ii %D is not one",ii);
715: KSPGetPC(k2[0],&pc2);
716: PCSetType(pc2, PCLU);
717: PCFactorSetShiftType(pc2,MAT_SHIFT_INBLOCKS);
718: KSPSetTolerances(k2[0],PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,1);
719: KSPSetType(k2[0], KSPPREONLY);
720: /* This flag gets reset by PCBJacobiGetSubKSP(), but our BJacobi really does the same algorithm everywhere (and in
721: * fact, all but one process will have zero dofs), so we reset the flag to avoid having PCView_BJacobi attempt to
722: * view every subdomain as though they were different. */
723: ((PC_BJacobi*)subpc->data)->same_local_solves = PETSC_TRUE;
724: }
726: /* should be called in PCSetFromOptions_GAMG(), but cannot be called prior to PCMGSetLevels() */
727: PetscObjectOptionsBegin((PetscObject)pc);
728: PCSetFromOptions_MG(PetscOptionsObject,pc);
729: PetscOptionsEnd();
730: if (!mg->galerkin) SETERRQ(comm,PETSC_ERR_USER,"PCGAMG must use Galerkin for coarse operators.");
731: if (mg->galerkin == 1) mg->galerkin = 2;
733: /* clean up */
734: for (level=1; level<pc_gamg->Nlevels; level++) {
735: MatDestroy(&Parr[level]);
736: MatDestroy(&Aarr[level]);
737: }
739: PCSetUp_MG(pc);
740: } else {
741: KSP smoother;
742: PetscInfo(pc,"One level solver used (system is seen as DD). Using default solver.\n");
743: PCMGGetSmoother(pc, 0, &smoother);
744: KSPSetOperators(smoother, Aarr[0], Aarr[0]);
745: KSPSetType(smoother, KSPPREONLY);
746: PCSetUp_MG(pc);
747: }
748: return(0);
749: }
751: /* ------------------------------------------------------------------------- */
752: /*
753: PCDestroy_GAMG - Destroys the private context for the GAMG preconditioner
754: that was created with PCCreate_GAMG().
756: Input Parameter:
757: . pc - the preconditioner context
759: Application Interface Routine: PCDestroy()
760: */
763: PetscErrorCode PCDestroy_GAMG(PC pc)
764: {
766: PC_MG *mg = (PC_MG*)pc->data;
767: PC_GAMG *pc_gamg= (PC_GAMG*)mg->innerctx;
770: PCReset_GAMG(pc);
771: if (pc_gamg->ops->destroy) {
772: (*pc_gamg->ops->destroy)(pc);
773: }
774: PetscRandomDestroy(&pc_gamg->random);
775: PetscFree(pc_gamg->ops);
776: PetscFree(pc_gamg->gamg_type_name);
777: PetscFree(pc_gamg);
778: PCDestroy_MG(pc);
779: return(0);
780: }
785: /*@
786: PCGAMGSetProcEqLim - Set number of equations to aim for on coarse grids via processor reduction.
788: Logically Collective on PC
790: Input Parameters:
791: + pc - the preconditioner context
792: - n - the number of equations
795: Options Database Key:
796: . -pc_gamg_process_eq_limit <limit>
798: Level: intermediate
800: Concepts: Unstructured multigrid preconditioner
802: .seealso: PCGAMGSetCoarseEqLim()
803: @*/
804: PetscErrorCode PCGAMGSetProcEqLim(PC pc, PetscInt n)
805: {
810: PetscTryMethod(pc,"PCGAMGSetProcEqLim_C",(PC,PetscInt),(pc,n));
811: return(0);
812: }
816: static PetscErrorCode PCGAMGSetProcEqLim_GAMG(PC pc, PetscInt n)
817: {
818: PC_MG *mg = (PC_MG*)pc->data;
819: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
822: if (n>0) pc_gamg->min_eq_proc = n;
823: return(0);
824: }
828: /*@
829: PCGAMGSetCoarseEqLim - Set max number of equations on coarse grids.
831: Collective on PC
833: Input Parameters:
834: + pc - the preconditioner context
835: - n - maximum number of equations to aim for
837: Options Database Key:
838: . -pc_gamg_coarse_eq_limit <limit>
840: Level: intermediate
842: Concepts: Unstructured multigrid preconditioner
844: .seealso: PCGAMGSetProcEqLim()
845: @*/
846: PetscErrorCode PCGAMGSetCoarseEqLim(PC pc, PetscInt n)
847: {
852: PetscTryMethod(pc,"PCGAMGSetCoarseEqLim_C",(PC,PetscInt),(pc,n));
853: return(0);
854: }
858: static PetscErrorCode PCGAMGSetCoarseEqLim_GAMG(PC pc, PetscInt n)
859: {
860: PC_MG *mg = (PC_MG*)pc->data;
861: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
864: if (n>0) pc_gamg->coarse_eq_limit = n;
865: return(0);
866: }
870: /*@
871: PCGAMGSetRepartitioning - Repartition the coarse grids
873: Collective on PC
875: Input Parameters:
876: + pc - the preconditioner context
877: - n - PETSC_TRUE or PETSC_FALSE
879: Options Database Key:
880: . -pc_gamg_repartition <true,false>
882: Level: intermediate
884: Concepts: Unstructured multigrid preconditioner
886: .seealso: ()
887: @*/
888: PetscErrorCode PCGAMGSetRepartitioning(PC pc, PetscBool n)
889: {
894: PetscTryMethod(pc,"PCGAMGSetRepartitioning_C",(PC,PetscBool),(pc,n));
895: return(0);
896: }
900: static PetscErrorCode PCGAMGSetRepartitioning_GAMG(PC pc, PetscBool n)
901: {
902: PC_MG *mg = (PC_MG*)pc->data;
903: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
906: pc_gamg->repart = n;
907: return(0);
908: }
912: /*@
913: PCGAMGSetReuseInterpolation - Reuse prolongation when rebuilding preconditioner
915: Collective on PC
917: Input Parameters:
918: + pc - the preconditioner context
919: - n - PETSC_TRUE or PETSC_FALSE
921: Options Database Key:
922: . -pc_gamg_reuse_interpolation <true,false>
924: Level: intermediate
926: Concepts: Unstructured multigrid preconditioner
928: .seealso: ()
929: @*/
930: PetscErrorCode PCGAMGSetReuseInterpolation(PC pc, PetscBool n)
931: {
936: PetscTryMethod(pc,"PCGAMGSetReuseInterpolation_C",(PC,PetscBool),(pc,n));
937: return(0);
938: }
942: static PetscErrorCode PCGAMGSetReuseInterpolation_GAMG(PC pc, PetscBool n)
943: {
944: PC_MG *mg = (PC_MG*)pc->data;
945: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
948: pc_gamg->reuse_prol = n;
949: return(0);
950: }
954: /*@
955: PCGAMGSetUseASMAggs -
957: Collective on PC
959: Input Parameters:
960: . pc - the preconditioner context
963: Options Database Key:
964: . -pc_gamg_use_agg_gasm
966: Level: intermediate
968: Concepts: Unstructured multigrid preconditioner
970: .seealso: ()
971: @*/
972: PetscErrorCode PCGAMGSetUseASMAggs(PC pc, PetscBool n)
973: {
978: PetscTryMethod(pc,"PCGAMGSetUseASMAggs_C",(PC,PetscBool),(pc,n));
979: return(0);
980: }
984: static PetscErrorCode PCGAMGSetUseASMAggs_GAMG(PC pc, PetscBool n)
985: {
986: PC_MG *mg = (PC_MG*)pc->data;
987: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
990: pc_gamg->use_aggs_in_gasm = n;
991: return(0);
992: }
996: /*@
997: PCGAMGSetNlevels - Sets the maximum number of levels PCGAMG will use
999: Not collective on PC
1001: Input Parameters:
1002: + pc - the preconditioner
1003: - n - the maximum number of levels to use
1005: Options Database Key:
1006: . -pc_mg_levels
1008: Level: intermediate
1010: Concepts: Unstructured multigrid preconditioner
1012: .seealso: ()
1013: @*/
1014: PetscErrorCode PCGAMGSetNlevels(PC pc, PetscInt n)
1015: {
1020: PetscTryMethod(pc,"PCGAMGSetNlevels_C",(PC,PetscInt),(pc,n));
1021: return(0);
1022: }
1026: static PetscErrorCode PCGAMGSetNlevels_GAMG(PC pc, PetscInt n)
1027: {
1028: PC_MG *mg = (PC_MG*)pc->data;
1029: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1032: pc_gamg->Nlevels = n;
1033: return(0);
1034: }
1038: /*@
1039: PCGAMGSetThreshold - Relative threshold to use for dropping edges in aggregation graph
1041: Not collective on PC
1043: Input Parameters:
1044: + pc - the preconditioner context
1045: - threshold - the threshold value, 0.0 means keep all nonzero entries in the graph; negative means keep even zero entries in the graph
1047: Options Database Key:
1048: . -pc_gamg_threshold <threshold>
1050: Level: intermediate
1052: Concepts: Unstructured multigrid preconditioner
1054: .seealso: ()
1055: @*/
1056: PetscErrorCode PCGAMGSetThreshold(PC pc, PetscReal n)
1057: {
1062: PetscTryMethod(pc,"PCGAMGSetThreshold_C",(PC,PetscReal),(pc,n));
1063: return(0);
1064: }
1068: static PetscErrorCode PCGAMGSetThreshold_GAMG(PC pc, PetscReal n)
1069: {
1070: PC_MG *mg = (PC_MG*)pc->data;
1071: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1074: pc_gamg->threshold = n;
1075: return(0);
1076: }
1080: /*@C
1081: PCGAMGSetType - Set solution method
1083: Collective on PC
1085: Input Parameters:
1086: + pc - the preconditioner context
1087: - type - PCGAMGAGG, PCGAMGGEO, or PCGAMGCLASSICAL
1089: Options Database Key:
1090: . -pc_gamg_type <agg,geo,classical>
1092: Level: intermediate
1094: Concepts: Unstructured multigrid preconditioner
1096: .seealso: PCGAMGGetType(), PCGAMG
1097: @*/
1098: PetscErrorCode PCGAMGSetType(PC pc, PCGAMGType type)
1099: {
1104: PetscTryMethod(pc,"PCGAMGSetType_C",(PC,PCGAMGType),(pc,type));
1105: return(0);
1106: }
1110: /*@C
1111: PCGAMGGetType - Get solution method
1113: Collective on PC
1115: Input Parameter:
1116: . pc - the preconditioner context
1118: Output Parameter:
1119: . type - the type of algorithm used
1121: Level: intermediate
1123: Concepts: Unstructured multigrid preconditioner
1125: .seealso: PCGAMGSetType(), PCGAMGType
1126: @*/
1127: PetscErrorCode PCGAMGGetType(PC pc, PCGAMGType *type)
1128: {
1133: PetscUseMethod(pc,"PCGAMGGetType_C",(PC,PCGAMGType*),(pc,type));
1134: return(0);
1135: }
1139: static PetscErrorCode PCGAMGGetType_GAMG(PC pc, PCGAMGType *type)
1140: {
1141: PC_MG *mg = (PC_MG*)pc->data;
1142: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1145: *type = pc_gamg->type;
1146: return(0);
1147: }
1151: static PetscErrorCode PCGAMGSetType_GAMG(PC pc, PCGAMGType type)
1152: {
1153: PetscErrorCode ierr,(*r)(PC);
1154: PC_MG *mg = (PC_MG*)pc->data;
1155: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1158: pc_gamg->type = type;
1159: PetscFunctionListFind(GAMGList,type,&r);
1160: if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unknown GAMG type %s given",type);
1161: if (pc_gamg->ops->destroy) {
1162: (*pc_gamg->ops->destroy)(pc);
1163: PetscMemzero(pc_gamg->ops,sizeof(struct _PCGAMGOps));
1164: pc_gamg->ops->createlevel = PCGAMGCreateLevel_GAMG;
1165: /* cleaning up common data in pc_gamg - this should disapear someday */
1166: pc_gamg->data_cell_cols = 0;
1167: pc_gamg->data_cell_rows = 0;
1168: pc_gamg->orig_data_cell_cols = 0;
1169: pc_gamg->orig_data_cell_rows = 0;
1170: PetscFree(pc_gamg->data);
1171: pc_gamg->data_sz = 0;
1172: }
1173: PetscFree(pc_gamg->gamg_type_name);
1174: PetscStrallocpy(type,&pc_gamg->gamg_type_name);
1175: (*r)(pc);
1176: return(0);
1177: }
1181: static PetscErrorCode PCView_GAMG(PC pc,PetscViewer viewer)
1182: {
1184: PC_MG *mg = (PC_MG*)pc->data;
1185: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1188: PetscViewerASCIIPrintf(viewer," GAMG specific options\n");
1189: PetscViewerASCIIPrintf(viewer," Threshold for dropping small values from graph %g\n",(double)pc_gamg->threshold);
1190: if (pc_gamg->ops->view) {
1191: (*pc_gamg->ops->view)(pc,viewer);
1192: }
1193: return(0);
1194: }
1198: PetscErrorCode PCSetFromOptions_GAMG(PetscOptionItems *PetscOptionsObject,PC pc)
1199: {
1201: PC_MG *mg = (PC_MG*)pc->data;
1202: PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx;
1203: PetscBool flag;
1204: MPI_Comm comm;
1205: char prefix[256];
1206: const char *pcpre;
1209: PetscObjectGetComm((PetscObject)pc,&comm);
1210: PetscOptionsHead(PetscOptionsObject,"GAMG options");
1211: {
1212: char tname[256];
1213: PetscOptionsFList("-pc_gamg_type","Type of AMG method","PCGAMGSetType",GAMGList, pc_gamg->gamg_type_name, tname, sizeof(tname), &flag);
1214: if (flag) {
1215: PCGAMGSetType(pc,tname);
1216: }
1217: PetscOptionsBool("-pc_gamg_repartition","Repartion coarse grids","PCGAMGRepartitioning",pc_gamg->repart,&pc_gamg->repart,NULL);
1218: PetscOptionsBool("-pc_gamg_reuse_interpolation","Reuse prolongation operator","PCGAMGReuseInterpolation",pc_gamg->reuse_prol,&pc_gamg->reuse_prol,NULL);
1219: PetscOptionsBool("-pc_gamg_use_agg_gasm","Use aggregation agragates for GASM smoother","PCGAMGUseASMAggs",pc_gamg->use_aggs_in_gasm,&pc_gamg->use_aggs_in_gasm,NULL);
1220: PetscOptionsInt("-pc_gamg_process_eq_limit","Limit (goal) on number of equations per process on coarse grids","PCGAMGSetProcEqLim",pc_gamg->min_eq_proc,&pc_gamg->min_eq_proc,NULL);
1221: PetscOptionsInt("-pc_gamg_coarse_eq_limit","Limit on number of equations for the coarse grid","PCGAMGSetCoarseEqLim",pc_gamg->coarse_eq_limit,&pc_gamg->coarse_eq_limit,NULL);
1222: PetscOptionsReal("-pc_gamg_threshold","Relative threshold to use for dropping edges in aggregation graph","PCGAMGSetThreshold",pc_gamg->threshold,&pc_gamg->threshold,&flag);
1223: PetscOptionsInt("-pc_mg_levels","Set number of MG levels","PCGAMGSetNlevels",pc_gamg->Nlevels,&pc_gamg->Nlevels,NULL);
1225: /* set options for subtype */
1226: if (pc_gamg->ops->setfromoptions) {(*pc_gamg->ops->setfromoptions)(PetscOptionsObject,pc);}
1227: }
1228: PCGetOptionsPrefix(pc, &pcpre);
1229: PetscSNPrintf(prefix,sizeof(prefix),"%spc_gamg_",pcpre ? pcpre : "");
1230: PetscObjectSetOptionsPrefix((PetscObject)pc_gamg->random,prefix);
1231: PetscRandomSetFromOptions(pc_gamg->random);
1232: PetscOptionsTail();
1233: return(0);
1234: }
1236: /* -------------------------------------------------------------------------- */
1237: /*MC
1238: PCGAMG - Geometric algebraic multigrid (AMG) preconditioner
1240: Options Database Keys:
1241: Multigrid options(inherited)
1242: + -pc_mg_cycles <v>: v or w (PCMGSetCycleType())
1243: . -pc_mg_smoothup <1>: Number of post-smoothing steps (PCMGSetNumberSmoothUp)
1244: . -pc_mg_smoothdown <1>: Number of pre-smoothing steps (PCMGSetNumberSmoothDown)
1245: - -pc_mg_type <multiplicative>: (one of) additive multiplicative full kascade
1248: Notes: In order to obtain good performance for PCGAMG for vector valued problems you must
1249: $ Call MatSetBlockSize() to indicate the number of degrees of freedom per grid point
1250: $ Call MatSetNearNullSpace() (or PCSetCoordinates() if solving the equations of elasticity) to indicate the near null space of the operator
1251: $ See the Users Manual Chapter 4 for more details
1253: Level: intermediate
1255: Concepts: algebraic multigrid
1257: .seealso: PCCreate(), PCSetType(), MatSetBlockSize(), PCMGType, PCSetCoordinates(), MatSetNearNullSpace(), PCGAMGSetType(), PCGAMGAGG, PCGAMGGEO, PCGAMGCLASSICAL, PCGAMGSetProcEqLim(),
1258: PCGAMGSetCoarseEqLim(), PCGAMGSetRepartitioning(), PCGAMGRegister(), PCGAMGSetReuseInterpolation(), PCGAMGSetUseASMAggs(), PCGAMGSetNlevels(), PCGAMGSetThreshold(), PCGAMGGetType()
1259: M*/
1263: PETSC_EXTERN PetscErrorCode PCCreate_GAMG(PC pc)
1264: {
1266: PC_GAMG *pc_gamg;
1267: PC_MG *mg;
1270: /* register AMG type */
1271: PCGAMGInitializePackage();
1273: /* PCGAMG is an inherited class of PCMG. Initialize pc as PCMG */
1274: PCSetType(pc, PCMG);
1275: PetscObjectChangeTypeName((PetscObject)pc, PCGAMG);
1277: /* create a supporting struct and attach it to pc */
1278: PetscNewLog(pc,&pc_gamg);
1279: mg = (PC_MG*)pc->data;
1280: mg->galerkin = 2; /* Use Galerkin, but it is computed externally from PCMG by GAMG code */
1281: mg->innerctx = pc_gamg;
1283: PetscNewLog(pc,&pc_gamg->ops);
1285: pc_gamg->setup_count = 0;
1286: /* these should be in subctx but repartitioning needs simple arrays */
1287: pc_gamg->data_sz = 0;
1288: pc_gamg->data = 0;
1290: /* overwrite the pointers of PCMG by the functions of base class PCGAMG */
1291: pc->ops->setfromoptions = PCSetFromOptions_GAMG;
1292: pc->ops->setup = PCSetUp_GAMG;
1293: pc->ops->reset = PCReset_GAMG;
1294: pc->ops->destroy = PCDestroy_GAMG;
1295: mg->view = PCView_GAMG;
1297: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetProcEqLim_C",PCGAMGSetProcEqLim_GAMG);
1298: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetCoarseEqLim_C",PCGAMGSetCoarseEqLim_GAMG);
1299: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetRepartitioning_C",PCGAMGSetRepartitioning_GAMG);
1300: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetReuseInterpolation_C",PCGAMGSetReuseInterpolation_GAMG);
1301: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetUseASMAggs_C",PCGAMGSetUseASMAggs_GAMG);
1302: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetThreshold_C",PCGAMGSetThreshold_GAMG);
1303: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetType_C",PCGAMGSetType_GAMG);
1304: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGGetType_C",PCGAMGGetType_GAMG);
1305: PetscObjectComposeFunction((PetscObject)pc,"PCGAMGSetNlevels_C",PCGAMGSetNlevels_GAMG);
1306: pc_gamg->repart = PETSC_FALSE;
1307: pc_gamg->reuse_prol = PETSC_FALSE;
1308: pc_gamg->use_aggs_in_gasm = PETSC_FALSE;
1309: pc_gamg->min_eq_proc = 50;
1310: pc_gamg->coarse_eq_limit = 50;
1311: pc_gamg->threshold = 0.;
1312: pc_gamg->Nlevels = GAMG_MAXLEVELS;
1313: pc_gamg->current_level = 0; /* don't need to init really */
1314: pc_gamg->ops->createlevel = PCGAMGCreateLevel_GAMG;
1316: PetscRandomCreate(PetscObjectComm((PetscObject)pc),&pc_gamg->random);
1318: /* PCSetUp_GAMG assumes that the type has been set, so set it to the default now */
1319: PCGAMGSetType(pc,PCGAMGAGG);
1320: return(0);
1321: }
1325: /*@C
1326: PCGAMGInitializePackage - This function initializes everything in the PCGAMG package. It is called
1327: from PetscDLLibraryRegister() when using dynamic libraries, and on the first call to PCCreate_GAMG()
1328: when using static libraries.
1330: Level: developer
1332: .keywords: PC, PCGAMG, initialize, package
1333: .seealso: PetscInitialize()
1334: @*/
1335: PetscErrorCode PCGAMGInitializePackage(void)
1336: {
1340: if (PCGAMGPackageInitialized) return(0);
1341: PCGAMGPackageInitialized = PETSC_TRUE;
1342: PetscFunctionListAdd(&GAMGList,PCGAMGGEO,PCCreateGAMG_GEO);
1343: PetscFunctionListAdd(&GAMGList,PCGAMGAGG,PCCreateGAMG_AGG);
1344: PetscFunctionListAdd(&GAMGList,PCGAMGCLASSICAL,PCCreateGAMG_Classical);
1345: PetscRegisterFinalize(PCGAMGFinalizePackage);
1347: /* general events */
1348: PetscLogEventRegister("PCGAMGGraph_AGG", 0, &PC_GAMGGraph_AGG);
1349: PetscLogEventRegister("PCGAMGGraph_GEO", PC_CLASSID, &PC_GAMGGraph_GEO);
1350: PetscLogEventRegister("PCGAMGCoarse_AGG", PC_CLASSID, &PC_GAMGCoarsen_AGG);
1351: PetscLogEventRegister("PCGAMGCoarse_GEO", PC_CLASSID, &PC_GAMGCoarsen_GEO);
1352: PetscLogEventRegister("PCGAMGProl_AGG", PC_CLASSID, &PC_GAMGProlongator_AGG);
1353: PetscLogEventRegister("PCGAMGProl_GEO", PC_CLASSID, &PC_GAMGProlongator_GEO);
1354: PetscLogEventRegister("PCGAMGPOpt_AGG", PC_CLASSID, &PC_GAMGOptProlongator_AGG);
1356: #if defined PETSC_GAMG_USE_LOG
1357: PetscLogEventRegister("GAMG: createProl", PC_CLASSID, &petsc_gamg_setup_events[SET1]);
1358: PetscLogEventRegister(" Graph", PC_CLASSID, &petsc_gamg_setup_events[GRAPH]);
1359: /* PetscLogEventRegister(" G.Mat", PC_CLASSID, &petsc_gamg_setup_events[GRAPH_MAT]); */
1360: /* PetscLogEventRegister(" G.Filter", PC_CLASSID, &petsc_gamg_setup_events[GRAPH_FILTER]); */
1361: /* PetscLogEventRegister(" G.Square", PC_CLASSID, &petsc_gamg_setup_events[GRAPH_SQR]); */
1362: PetscLogEventRegister(" MIS/Agg", PC_CLASSID, &petsc_gamg_setup_events[SET4]);
1363: PetscLogEventRegister(" geo: growSupp", PC_CLASSID, &petsc_gamg_setup_events[SET5]);
1364: PetscLogEventRegister(" geo: triangle", PC_CLASSID, &petsc_gamg_setup_events[SET6]);
1365: PetscLogEventRegister(" search&set", PC_CLASSID, &petsc_gamg_setup_events[FIND_V]);
1366: PetscLogEventRegister(" SA: col data", PC_CLASSID, &petsc_gamg_setup_events[SET7]);
1367: PetscLogEventRegister(" SA: frmProl0", PC_CLASSID, &petsc_gamg_setup_events[SET8]);
1368: PetscLogEventRegister(" SA: smooth", PC_CLASSID, &petsc_gamg_setup_events[SET9]);
1369: PetscLogEventRegister("GAMG: partLevel", PC_CLASSID, &petsc_gamg_setup_events[SET2]);
1370: PetscLogEventRegister(" repartition", PC_CLASSID, &petsc_gamg_setup_events[SET12]);
1371: PetscLogEventRegister(" Invert-Sort", PC_CLASSID, &petsc_gamg_setup_events[SET13]);
1372: PetscLogEventRegister(" Move A", PC_CLASSID, &petsc_gamg_setup_events[SET14]);
1373: PetscLogEventRegister(" Move P", PC_CLASSID, &petsc_gamg_setup_events[SET15]);
1375: /* PetscLogEventRegister(" PL move data", PC_CLASSID, &petsc_gamg_setup_events[SET13]); */
1376: /* PetscLogEventRegister("GAMG: fix", PC_CLASSID, &petsc_gamg_setup_events[SET10]); */
1377: /* PetscLogEventRegister("GAMG: set levels", PC_CLASSID, &petsc_gamg_setup_events[SET11]); */
1378: /* create timer stages */
1379: #if defined GAMG_STAGES
1380: {
1381: char str[32];
1382: PetscInt lidx;
1383: sprintf(str,"MG Level %d (finest)",0);
1384: PetscLogStageRegister(str, &gamg_stages[0]);
1385: for (lidx=1; lidx<9; lidx++) {
1386: sprintf(str,"MG Level %d",lidx);
1387: PetscLogStageRegister(str, &gamg_stages[lidx]);
1388: }
1389: }
1390: #endif
1391: #endif
1392: return(0);
1393: }
1397: /*@C
1398: PCGAMGFinalizePackage - This function frees everything from the PCGAMG package. It is
1399: called from PetscFinalize() automatically.
1401: Level: developer
1403: .keywords: Petsc, destroy, package
1404: .seealso: PetscFinalize()
1405: @*/
1406: PetscErrorCode PCGAMGFinalizePackage(void)
1407: {
1411: PCGAMGPackageInitialized = PETSC_FALSE;
1412: PetscFunctionListDestroy(&GAMGList);
1413: return(0);
1414: }
1418: /*@C
1419: PCGAMGRegister - Register a PCGAMG implementation.
1421: Input Parameters:
1422: + type - string that will be used as the name of the GAMG type.
1423: - create - function for creating the gamg context.
1425: Level: advanced
1427: .seealso: PCGAMGType, PCGAMG, PCGAMGSetType()
1428: @*/
1429: PetscErrorCode PCGAMGRegister(PCGAMGType type, PetscErrorCode (*create)(PC))
1430: {
1434: PCGAMGInitializePackage();
1435: PetscFunctionListAdd(&GAMGList,type,create);
1436: return(0);
1437: }