1 /* 2 GAMG geometric-algebric multiogrid PC - Mark Adams 2011 3 */ 4 #include <../src/ksp/pc/impls/gamg/gamg.h> 5 6 PetscLogEvent gamg_setup_stages[NUM_SET]; 7 8 /* Private context for the GAMG preconditioner */ 9 typedef struct gamg_TAG { 10 PetscInt m_dim; 11 PetscInt m_Nlevels; 12 PetscInt m_data_sz; 13 PetscReal *m_data; /* blocked vector of vertex data on fine grid (coordinates) */ 14 } PC_GAMG; 15 16 #define TOP_GRID_LIM 100 17 18 /* -----------------------------------------------------------------------------*/ 19 #undef __FUNCT__ 20 #define __FUNCT__ "PCReset_GAMG" 21 PetscErrorCode PCReset_GAMG(PC pc) 22 { 23 PetscErrorCode ierr; 24 PC_MG *mg = (PC_MG*)pc->data; 25 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 26 27 PetscFunctionBegin; 28 ierr = PetscFree(pc_gamg->m_data);CHKERRQ(ierr); 29 pc_gamg->m_data = 0; pc_gamg->m_data_sz = 0; 30 PetscFunctionReturn(0); 31 } 32 33 /* -------------------------------------------------------------------------- */ 34 /* 35 PCSetCoordinates_GAMG 36 37 Input Parameter: 38 . pc - the preconditioner context 39 */ 40 EXTERN_C_BEGIN 41 #undef __FUNCT__ 42 #define __FUNCT__ "PCSetCoordinates_GAMG" 43 PetscErrorCode PCSetCoordinates_GAMG( PC a_pc, PetscInt a_ndm, PetscReal *a_coords ) 44 { 45 PC_MG *mg = (PC_MG*)a_pc->data; 46 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 47 PetscErrorCode ierr; 48 PetscInt arrsz,bs,my0,kk,ii,jj,nloc,sz,M; 49 Mat Amat = a_pc->pmat; 50 PetscBool useSA = PETSC_FALSE, flag; 51 char str[16]; 52 53 PetscFunctionBegin; 54 ierr = MatGetBlockSize( Amat, &bs ); CHKERRQ( ierr ); 55 ierr = MatGetOwnershipRange( Amat, &my0, &kk ); CHKERRQ(ierr); 56 nloc = (kk-my0)/bs; M = kk - my0; 57 if((kk-my0)%bs!=0) SETERRQ1(((PetscObject)Amat)->comm,PETSC_ERR_ARG_WRONG, "Bad local size %d.",nloc); 58 59 ierr = PetscOptionsGetString(PETSC_NULL,"-pc_gamg_type",str,16,&flag); CHKERRQ( ierr ); 60 useSA = (PetscBool)(flag && strcmp(str,"sa") == 0); 61 62 if(a_coords == 0) useSA = PETSC_TRUE; /* use SA if no data */ 63 if( !useSA ) sz = a_ndm; /* coordinates */ 64 else{ /* SA: null space vectors */ 65 if(a_coords != 0) sz = (a_ndm==2 ? 3*bs : 6*bs); /* elasticity */ 66 else sz = bs*bs; /* no data, force SA with constant null space vectors */ 67 if(a_coords != 0 && bs==1 ) sz = 1; /* scalar problem with coords and SA (not needed) */ 68 } 69 arrsz = nloc*sz; 70 71 /* create data - syntactic sugar that should be refactored at some point */ 72 if (!pc_gamg->m_data || (pc_gamg->m_data_sz != arrsz)) { 73 ierr = PetscFree( pc_gamg->m_data ); CHKERRQ(ierr); 74 ierr = PetscMalloc((arrsz+1)*sizeof(double), &pc_gamg->m_data ); CHKERRQ(ierr); 75 } 76 for(kk=0;kk<arrsz;kk++)pc_gamg->m_data[kk] = -999.; 77 pc_gamg->m_data[arrsz] = -99.; 78 /* copy data in - column oriented */ 79 if( useSA ) { 80 for(kk=0;kk<nloc;kk++){ 81 PetscReal *data = &pc_gamg->m_data[kk*bs]; 82 if( sz==1 ) *data = 1.0; 83 else { 84 for(ii=0;ii<bs;ii++) 85 for(jj=0;jj<bs;jj++) 86 if(ii==jj)data[ii*M + jj] = 1.0; /* translational modes */ 87 else data[ii*M + jj] = 0.0; 88 if( a_coords != 0 ) { 89 if( a_ndm == 2 ){ /* rotational modes */ 90 data += 2*M; 91 data[0] = -a_coords[2*kk+1]; 92 data[1] = a_coords[2*kk]; 93 } 94 else { 95 data += 3*M; 96 data[0] = 0.0; data[M+0] = a_coords[3*kk+2]; data[2*M+0] = -a_coords[3*kk+1]; 97 data[1] = -a_coords[3*kk+2]; data[M+1] = 0.0; data[2*M+1] = a_coords[3*kk]; 98 data[2] = a_coords[3*kk+1]; data[M+2] = -a_coords[3*kk]; data[2*M+2] = 0.0; 99 } 100 } 101 } 102 } 103 } 104 else { 105 for( kk = 0 ; kk < nloc ; kk++ ){ 106 for( ii = 0 ; ii < a_ndm ; ii++ ) { 107 pc_gamg->m_data[ii*nloc + kk] = a_coords[kk*a_ndm + ii]; 108 } 109 } 110 } 111 112 assert(pc_gamg->m_data[arrsz] == -99.); 113 for(kk=0;kk<arrsz;kk++){ 114 assert(pc_gamg->m_data[kk] != -999.); // debug 115 } 116 117 pc_gamg->m_data_sz = arrsz; 118 pc_gamg->m_dim = a_ndm; 119 120 PetscFunctionReturn(0); 121 } 122 EXTERN_C_END 123 124 /* -------------------------------------------------------------------------- */ 125 /* 126 partitionLevel 127 128 Input Parameter: 129 . a_Amat_fine - matrix on this fine (k) level 130 . a_data_sz - size of data to move (coarse grid) 131 In/Output Parameter: 132 . a_P_inout - prolongation operator to the next level (k-1) 133 . a_coarse_data - data that need to be moved 134 . a_active_proc - number of active procs 135 Output Parameter: 136 . a_Amat_crs - coarse matrix that is created (k-1) 137 */ 138 139 #undef __FUNCT__ 140 #define __FUNCT__ "partitionLevel" 141 PetscErrorCode partitionLevel( Mat a_Amat_fine, 142 PetscInt a_data_sz, 143 PetscInt a_cbs, 144 Mat *a_P_inout, 145 PetscReal **a_coarse_data, 146 PetscMPIInt *a_active_proc, 147 Mat *a_Amat_crs 148 ) 149 { 150 PetscErrorCode ierr; 151 Mat Cmat,Pnew,Pold=*a_P_inout; 152 IS new_indices,isnum; 153 MPI_Comm wcomm = ((PetscObject)a_Amat_fine)->comm; 154 PetscMPIInt nactive_procs,mype,npe; 155 PetscInt Istart,Iend,Istart0,Iend0,ncrs0,ncrs_new,fbs; 156 157 PetscFunctionBegin; 158 ierr = MPI_Comm_rank(wcomm,&mype);CHKERRQ(ierr); 159 ierr = MPI_Comm_size(wcomm,&npe);CHKERRQ(ierr); 160 ierr = MatGetBlockSize( a_Amat_fine, &fbs ); CHKERRQ(ierr); 161 /* RAP */ 162 ierr = MatPtAP( a_Amat_fine, Pold, MAT_INITIAL_MATRIX, 2.0, &Cmat ); CHKERRQ(ierr); 163 ierr = MatSetBlockSize( Cmat, a_cbs ); CHKERRQ(ierr); 164 165 ierr = MatGetOwnershipRange( Cmat, &Istart0, &Iend0 ); CHKERRQ(ierr); 166 ncrs0 = (Iend0-Istart0)/a_cbs; assert( (Iend0-Istart0)%a_cbs == 0 ); 167 168 /* Repartition Cmat_{k} and move colums of P^{k}_{k-1} and coordinates accordingly */ 169 { 170 PetscInt neq,NN,counts[npe]; 171 IS isnewproc; 172 PetscMPIInt new_npe,targ_npe; 173 174 ierr = MatGetSize( Cmat, &neq, &NN );CHKERRQ(ierr); 175 #define MIN_EQ_PROC 100 176 nactive_procs = *a_active_proc; 177 targ_npe = neq/MIN_EQ_PROC; /* hardwire min. number of eq/proc */ 178 if( targ_npe == 0 || neq < TOP_GRID_LIM ) new_npe = 1; /* chop coarsest grid */ 179 else if (targ_npe >= nactive_procs ) new_npe = nactive_procs; /* no change */ 180 else { 181 PetscMPIInt factstart,fact; 182 new_npe = -9999; 183 factstart = nactive_procs; 184 for(fact=factstart;fact>0;fact--){ /* try to find a better number of procs */ 185 if( nactive_procs%fact==0 && neq/(nactive_procs/fact) > MIN_EQ_PROC ) { 186 new_npe = nactive_procs/fact; 187 } 188 } 189 if(new_npe == -9999) new_npe = nactive_procs; 190 } 191 *a_active_proc = new_npe; /* output for next time */ 192 { /* partition: get 'isnewproc' */ 193 MatPartitioning mpart; 194 Mat adj; 195 const PetscInt *is_idx; 196 PetscInt is_sz,kk,jj,ii,old_fact=(npe/nactive_procs),new_fact=(npe/new_npe),*isnewproc_idx; 197 /* create sub communicator */ 198 MPI_Comm cm,new_comm; 199 int membershipKey = mype % old_fact; 200 ierr = MPI_Comm_split(wcomm, membershipKey, mype, &cm); CHKERRQ(ierr); 201 ierr = PetscCommDuplicate( cm, &new_comm, PETSC_NULL ); CHKERRQ(ierr); 202 ierr = MPI_Comm_free( &cm ); CHKERRQ(ierr); 203 204 /* MatPartitioningApply call MatConvert, which is collective */ 205 if( a_cbs==1) { 206 ierr = MatConvert( Cmat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj ); CHKERRQ(ierr); 207 } 208 else { 209 /* make a scalar matrix to partition */ 210 Mat tMat; 211 PetscInt Ii,ncols; const PetscScalar *vals; const PetscInt *idx; 212 ierr = MatCreateMPIAIJ( wcomm, ncrs0, ncrs0, 213 PETSC_DETERMINE, PETSC_DETERMINE, 214 25, PETSC_NULL, 10, PETSC_NULL, 215 &tMat ); 216 217 for ( Ii = Istart0; Ii < Iend0; Ii++ ) { 218 PetscInt dest_row = Ii/a_cbs; 219 ierr = MatGetRow(Cmat,Ii,&ncols,&idx,&vals); CHKERRQ(ierr); 220 for( jj = 0 ; jj < ncols ; jj++ ){ 221 PetscInt dest_col = idx[jj]/a_cbs; 222 PetscScalar v = 1.0; 223 ierr = MatSetValues(tMat,1,&dest_row,1,&dest_col,&v,ADD_VALUES); CHKERRQ(ierr); 224 } 225 ierr = MatRestoreRow(Cmat,Ii,&ncols,&idx,&vals); CHKERRQ(ierr); 226 } 227 ierr = MatAssemblyBegin(tMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 228 ierr = MatAssemblyEnd(tMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 229 230 ierr = MatConvert( tMat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj ); CHKERRQ(ierr); 231 232 ierr = MatDestroy( &tMat ); CHKERRQ(ierr); 233 } 234 if( membershipKey == 0 ) { 235 if(ncrs0==0)SETERRQ(wcomm,PETSC_ERR_LIB,"zero local nodes -- increase min"); 236 /* hack to fix global data that pmetis.c uses in 'adj' */ 237 for( kk=0 , jj=0 ; kk<=npe ; jj++, kk += old_fact ) { 238 adj->rmap->range[jj] = adj->rmap->range[kk]; 239 } 240 ierr = MatPartitioningCreate( new_comm, &mpart ); CHKERRQ(ierr); 241 ierr = MatPartitioningSetAdjacency( mpart, adj ); CHKERRQ(ierr); 242 ierr = MatPartitioningSetFromOptions( mpart ); CHKERRQ(ierr); 243 ierr = MatPartitioningSetNParts( mpart, new_npe ); CHKERRQ(ierr); 244 ierr = MatPartitioningApply( mpart, &isnewproc ); CHKERRQ(ierr); 245 ierr = MatPartitioningDestroy( &mpart ); CHKERRQ(ierr); 246 /* collect IS info */ 247 ierr = ISGetLocalSize( isnewproc, &is_sz ); CHKERRQ(ierr); 248 ierr = PetscMalloc( a_cbs*is_sz*sizeof(PetscInt), &isnewproc_idx ); CHKERRQ(ierr); 249 ierr = ISGetIndices( isnewproc, &is_idx ); CHKERRQ(ierr); 250 /* spread partitioning across machine - probably the right thing to do but machine spec. */ 251 for(kk=0,jj=0;kk<is_sz;kk++){ 252 for(ii=0 ; ii<a_cbs ; ii++, jj++ ) { /* expand for equation level by 'bs' */ 253 isnewproc_idx[jj] = is_idx[kk] * new_fact; 254 } 255 } 256 ierr = ISRestoreIndices( isnewproc, &is_idx ); CHKERRQ(ierr); 257 ierr = ISDestroy( &isnewproc ); CHKERRQ(ierr); 258 is_sz *= a_cbs; 259 } 260 else { 261 isnewproc_idx = 0; 262 is_sz = 0; 263 } 264 ierr = MatDestroy( &adj ); CHKERRQ(ierr); 265 ierr = MPI_Comm_free( &new_comm ); CHKERRQ(ierr); 266 ierr = ISCreateGeneral( wcomm, is_sz, isnewproc_idx, PETSC_COPY_VALUES, &isnewproc ); 267 if( membershipKey == 0 ) { 268 ierr = PetscFree( isnewproc_idx ); CHKERRQ(ierr); 269 } 270 } 271 /* 272 Create an index set from the isnewproc index set to indicate the mapping TO 273 */ 274 ierr = ISPartitioningToNumbering( isnewproc, &isnum ); CHKERRQ(ierr); 275 /* 276 Determine how many elements are assigned to each processor 277 */ 278 ierr = ISPartitioningCount( isnewproc, npe, counts ); CHKERRQ(ierr); 279 ierr = ISDestroy( &isnewproc ); CHKERRQ(ierr); 280 ncrs_new = counts[mype]/a_cbs; 281 } 282 283 { /* Create a vector to contain the newly ordered element information */ 284 const PetscInt *idx; 285 PetscInt ii,jj,kk; 286 IS isscat; 287 PetscScalar *array; 288 Vec src_crd, dest_crd; 289 PetscReal *data = *a_coarse_data; 290 VecScatter vecscat; 291 PetscInt tidx[ncrs0*a_data_sz]; 292 293 ierr = VecCreate( wcomm, &dest_crd ); 294 ierr = VecSetSizes( dest_crd, a_data_sz*ncrs_new, PETSC_DECIDE ); CHKERRQ(ierr); 295 ierr = VecSetFromOptions( dest_crd ); CHKERRQ(ierr); /*funny vector-get global options?*/ 296 /* 297 There are 'a_data_sz' data items per node, (one can think of the vectors of having a 298 block size of 'a_data_sz'). Note, ISs are expanded into equation space by 'a_cbs'. 299 */ 300 ierr = ISGetIndices( isnum, &idx ); CHKERRQ(ierr); 301 for(ii=0,jj=0; ii<ncrs0 ; ii++) { 302 PetscInt id = idx[ii*a_cbs]/a_cbs; 303 for( kk=0; kk<a_data_sz ; kk++, jj++) tidx[jj] = id*a_data_sz + kk; 304 } 305 ierr = ISRestoreIndices( isnum, &idx ); CHKERRQ(ierr); 306 ierr = ISCreateGeneral( wcomm, a_data_sz*ncrs0, tidx, PETSC_COPY_VALUES, &isscat ); 307 CHKERRQ(ierr); 308 /* 309 Create a vector to contain the original vertex information for each element 310 */ 311 ierr = VecCreateSeq( PETSC_COMM_SELF, a_data_sz*ncrs0, &src_crd ); CHKERRQ(ierr); 312 for(ii=0, jj=0; ii<ncrs0 ; ii++) { 313 for( kk=0; kk < a_data_sz ; kk++, jj++) { 314 ierr = VecSetValues( src_crd, 1, &jj, &data[kk*ncrs0 + ii], INSERT_VALUES ); CHKERRQ(ierr); 315 } 316 } 317 ierr = VecAssemblyBegin(src_crd); CHKERRQ(ierr); 318 ierr = VecAssemblyEnd(src_crd); CHKERRQ(ierr); 319 /* 320 Scatter the element vertex information (still in the original vertex ordering) 321 to the correct processor 322 */ 323 ierr = VecScatterCreate( src_crd, PETSC_NULL, dest_crd, isscat, &vecscat); 324 CHKERRQ(ierr); 325 ierr = ISDestroy( &isscat ); CHKERRQ(ierr); 326 ierr = VecScatterBegin(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 327 ierr = VecScatterEnd(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 328 ierr = VecScatterDestroy( &vecscat ); CHKERRQ(ierr); 329 ierr = VecDestroy( &src_crd ); CHKERRQ(ierr); 330 /* 331 Put the element vertex data into a new allocation of the gdata->ele 332 */ 333 ierr = PetscFree( *a_coarse_data ); CHKERRQ(ierr); 334 ierr = PetscMalloc( a_data_sz*ncrs_new*sizeof(PetscReal), a_coarse_data ); CHKERRQ(ierr); 335 VecGetLocalSize( dest_crd, &ii ); assert(ii==a_data_sz*ncrs_new); 336 337 ierr = VecGetArray( dest_crd, &array ); CHKERRQ(ierr); 338 data = *a_coarse_data; 339 for(ii=0, jj=0; ii<ncrs_new ; ii++) { 340 for( kk=0; kk < a_data_sz ; kk++, jj++) { 341 data[kk*ncrs_new + ii] = PetscRealPart(array[jj]); 342 } 343 } 344 ierr = VecRestoreArray( dest_crd, &array ); CHKERRQ(ierr); 345 ierr = VecDestroy( &dest_crd ); CHKERRQ(ierr); 346 } 347 /* 348 Invert for MatGetSubMatrix 349 */ 350 ierr = ISInvertPermutation( isnum, ncrs_new*a_cbs, &new_indices ); CHKERRQ(ierr); 351 ierr = ISSort( new_indices ); CHKERRQ(ierr); /* is this needed? */ 352 ierr = ISDestroy( &isnum ); CHKERRQ(ierr); 353 /* A_crs output */ 354 ierr = MatGetSubMatrix( Cmat, new_indices, new_indices, MAT_INITIAL_MATRIX, a_Amat_crs ); 355 CHKERRQ(ierr); 356 357 ierr = MatDestroy( &Cmat ); CHKERRQ(ierr); 358 Cmat = *a_Amat_crs; 359 ierr = MatSetBlockSize( Cmat, a_cbs ); CHKERRQ(ierr); 360 361 /* prolongator */ 362 ierr = MatGetOwnershipRange( Pold, &Istart, &Iend ); CHKERRQ(ierr); 363 { 364 IS findices; 365 ierr = ISCreateStride(wcomm,Iend-Istart,Istart,1,&findices); CHKERRQ(ierr); 366 ierr = MatGetSubMatrix( Pold, findices, new_indices, MAT_INITIAL_MATRIX, &Pnew ); 367 CHKERRQ(ierr); 368 ierr = ISDestroy( &findices ); CHKERRQ(ierr); 369 } 370 ierr = MatDestroy( a_P_inout ); CHKERRQ(ierr); 371 *a_P_inout = Pnew; /* output */ 372 ierr = ISDestroy( &new_indices ); CHKERRQ(ierr); 373 374 PetscFunctionReturn(0); 375 } 376 377 #define GAMG_MAXLEVELS 2 378 #if defined(PETSC_USE_LOG) 379 PetscLogStage gamg_stages[20]; 380 #endif 381 /* -------------------------------------------------------------------------- */ 382 /* 383 PCSetUp_GAMG - Prepares for the use of the GAMG preconditioner 384 by setting data structures and options. 385 386 Input Parameter: 387 . pc - the preconditioner context 388 389 Application Interface Routine: PCSetUp() 390 391 Notes: 392 The interface routine PCSetUp() is not usually called directly by 393 the user, but instead is called by PCApply() if necessary. 394 */ 395 #undef __FUNCT__ 396 #define __FUNCT__ "PCSetUp_GAMG" 397 PetscErrorCode PCSetUp_GAMG( PC a_pc ) 398 { 399 PetscErrorCode ierr; 400 PC_MG *mg = (PC_MG*)a_pc->data; 401 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 402 Mat Amat = a_pc->mat, Pmat = a_pc->pmat; 403 PetscInt fine_level, level, level1, M, N, bs, nloc, lidx, data_sz, Istart, Iend; 404 MPI_Comm wcomm = ((PetscObject)a_pc)->comm; 405 PetscMPIInt mype,npe,nactivepe; 406 PetscBool isOK; 407 Mat Aarr[GAMG_MAXLEVELS], Parr[GAMG_MAXLEVELS]; 408 PetscReal *coarse_data = 0, *data, emaxs[GAMG_MAXLEVELS]; 409 410 PetscFunctionBegin; 411 if( a_pc->setupcalled ) { 412 /* no state data in GAMG to destroy */ 413 ierr = PCReset_MG( a_pc ); CHKERRQ(ierr); 414 } 415 ierr = MPI_Comm_rank(wcomm,&mype);CHKERRQ(ierr); 416 ierr = MPI_Comm_size(wcomm,&npe);CHKERRQ(ierr); 417 /* GAMG requires input of fine-grid matrix. It determines nlevels. */ 418 ierr = MatGetBlockSize( Amat, &bs ); CHKERRQ(ierr); 419 ierr = MatGetSize( Amat, &M, &N );CHKERRQ(ierr); 420 ierr = MatGetOwnershipRange( Amat, &Istart, &Iend ); CHKERRQ(ierr); 421 nloc = (Iend-Istart)/bs; assert((Iend-Istart)%bs == 0); 422 423 /* get data of not around */ 424 if( pc_gamg->m_data == 0 && nloc > 0 ) { 425 ierr = PCSetCoordinates_GAMG( a_pc, -1, 0 ); CHKERRQ( ierr ); 426 } 427 data = pc_gamg->m_data; 428 data_sz = pc_gamg->m_data_sz/nloc; assert(data!=0 || data_sz==0); 429 430 /* Get A_i and R_i */ 431 PetscPrintf(PETSC_COMM_WORLD,"\t[%d]%s level %d N=%d, data size=%d m_data_sz=%d nloc=%d\n",0,__FUNCT__,0,N,data_sz,pc_gamg->m_data_sz,nloc); 432 for ( level=0, Aarr[0] = Pmat, nactivepe = npe; /* hard wired stopping logic */ 433 level < GAMG_MAXLEVELS-1 && (level==0 || M/bs>TOP_GRID_LIM) && (npe==1 || nactivepe>1); 434 level++ ) { 435 level1 = level + 1; 436 ierr = PetscLogEventBegin(gamg_setup_stages[SET1],0,0,0,0);CHKERRQ(ierr); 437 ierr = createProlongation( Aarr[level], data, pc_gamg->m_dim, &bs, &data_sz, 438 &Parr[level1], &coarse_data, &isOK, &emaxs[level] ); 439 CHKERRQ(ierr); 440 ierr = PetscLogEventEnd(gamg_setup_stages[SET1],0,0,0,0);CHKERRQ(ierr); 441 442 ierr = PetscFree( data ); CHKERRQ( ierr ); 443 if(level==0) Aarr[0] = Amat; /* use Pmat for finest level setup, but use mat for solver */ 444 if( isOK ) { 445 ierr = PetscLogEventBegin(gamg_setup_stages[SET2],0,0,0,0);CHKERRQ(ierr); 446 ierr = partitionLevel( Aarr[level], data_sz, bs, 447 &Parr[level1], &coarse_data, &nactivepe, &Aarr[level1] ); 448 CHKERRQ(ierr); 449 ierr = PetscLogEventEnd(gamg_setup_stages[SET2],0,0,0,0);CHKERRQ(ierr); 450 ierr = MatGetSize( Aarr[level1], &M, &N );CHKERRQ(ierr); 451 PetscPrintf(PETSC_COMM_WORLD,"\t\t[%d]%s %d) N=%d, %d data size, %d active pes\n",0,__FUNCT__,level1,N,data_sz,nactivepe); 452 } 453 else{ 454 break; 455 } 456 data = coarse_data; 457 } 458 ierr = PetscFree( coarse_data ); CHKERRQ( ierr ); 459 PetscPrintf(PETSC_COMM_WORLD,"\t[%d]%s %d levels\n",0,__FUNCT__,level + 1); 460 pc_gamg->m_data = 0; /* destroyed coordinate data */ 461 pc_gamg->m_Nlevels = level + 1; 462 fine_level = level; 463 ierr = PCMGSetLevels(a_pc,pc_gamg->m_Nlevels,PETSC_NULL);CHKERRQ(ierr); 464 465 /* set default smoothers */ 466 for ( lidx=1, level = pc_gamg->m_Nlevels-2; 467 lidx <= fine_level; 468 lidx++, level--) { 469 PetscReal emax, emin; 470 KSP smoother; PC subpc; 471 ierr = PCMGGetSmoother( a_pc, lidx, &smoother ); CHKERRQ(ierr); 472 ierr = KSPSetType( smoother, KSPCHEBYCHEV );CHKERRQ(ierr); 473 if( emaxs[level] > 0.0 ) emax = emaxs[level]; 474 else{ /* eigen estimate 'emax' */ 475 KSP eksp; Mat Lmat = Aarr[level]; 476 Vec bb, xx; PC pc; 477 478 ierr = MatGetVecs( Lmat, &bb, 0 ); CHKERRQ(ierr); 479 ierr = MatGetVecs( Lmat, &xx, 0 ); CHKERRQ(ierr); 480 { 481 PetscRandom rctx; 482 ierr = PetscRandomCreate(wcomm,&rctx);CHKERRQ(ierr); 483 ierr = PetscRandomSetFromOptions(rctx);CHKERRQ(ierr); 484 ierr = VecSetRandom(bb,rctx);CHKERRQ(ierr); 485 ierr = PetscRandomDestroy( &rctx ); CHKERRQ(ierr); 486 } 487 ierr = KSPCreate(wcomm,&eksp);CHKERRQ(ierr); 488 ierr = KSPSetInitialGuessNonzero( eksp, PETSC_FALSE ); CHKERRQ(ierr); 489 ierr = KSPSetOperators( eksp, Lmat, Lmat, DIFFERENT_NONZERO_PATTERN ); CHKERRQ( ierr ); 490 ierr = KSPGetPC( eksp, &pc );CHKERRQ( ierr ); 491 ierr = PCSetType( pc, PCJACOBI ); CHKERRQ(ierr); /* should be same as above */ 492 ierr = KSPSetTolerances( eksp, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT, 10 ); 493 CHKERRQ(ierr); 494 ierr = KSPSetConvergenceTest( eksp, KSPSkipConverged, 0, 0 ); CHKERRQ(ierr); 495 ierr = KSPSetNormType( eksp, KSP_NORM_NONE ); CHKERRQ(ierr); 496 497 ierr = KSPSetComputeSingularValues( eksp,PETSC_TRUE ); CHKERRQ(ierr); 498 ierr = KSPSolve( eksp, bb, xx ); CHKERRQ(ierr); 499 ierr = KSPComputeExtremeSingularValues( eksp, &emax, &emin ); CHKERRQ(ierr); 500 ierr = VecDestroy( &xx ); CHKERRQ(ierr); 501 ierr = VecDestroy( &bb ); CHKERRQ(ierr); 502 ierr = KSPDestroy( &eksp ); CHKERRQ(ierr); 503 } 504 { 505 PetscInt N1, N0, tt; 506 ierr = MatGetSize( Aarr[level], &N1, &tt ); CHKERRQ(ierr); 507 ierr = MatGetSize( Aarr[level+1], &N0, &tt ); CHKERRQ(ierr); 508 emin = 1.5*emax/((PetscReal)N1/(PetscReal)N0); /* this should be about the coarsening rate */ 509 PetscPrintf(PETSC_COMM_WORLD,"\t\t\t%s max eigen = %e min = %e (N=%d)\n",__FUNCT__,emax,emin,N1/bs); 510 emax *= 1.05; 511 } 512 513 ierr = KSPSetOperators( smoother, Aarr[level], Aarr[level], DIFFERENT_NONZERO_PATTERN ); 514 ierr = KSPChebychevSetEigenvalues( smoother, emax, emin );CHKERRQ(ierr); 515 ierr = KSPGetPC( smoother, &subpc ); CHKERRQ(ierr); 516 ierr = PCSetType( subpc, PCJACOBI ); CHKERRQ(ierr); 517 ierr = KSPSetNormType( smoother, KSP_NORM_NONE ); CHKERRQ(ierr); 518 } 519 { 520 KSP smoother; /* coarse grid */ 521 Mat Lmat = Aarr[pc_gamg->m_Nlevels-1]; 522 ierr = PCMGGetSmoother( a_pc, 0, &smoother ); CHKERRQ(ierr); 523 ierr = KSPSetOperators( smoother, Lmat, Lmat, DIFFERENT_NONZERO_PATTERN ); 524 CHKERRQ(ierr); 525 ierr = KSPSetNormType( smoother, KSP_NORM_NONE ); CHKERRQ(ierr); 526 } 527 /* should be called in PCSetFromOptions_GAMG(), but cannot be called prior to PCMGSetLevels() */ 528 ierr = PCSetFromOptions_MG(a_pc); CHKERRQ(ierr); 529 { 530 PetscBool galerkin; 531 ierr = PCMGGetGalerkin( a_pc, &galerkin); CHKERRQ(ierr); 532 if(galerkin){ 533 SETERRQ(wcomm,PETSC_ERR_ARG_WRONG, "GAMG does galerkin manually so it must not be used in PC_MG."); 534 } 535 } 536 537 /* set interpolation between the levels, create timer stages, clean up */ 538 if( PETSC_FALSE ) { 539 char str[32]; 540 sprintf(str,"MG Level %d (%d)",0,pc_gamg->m_Nlevels-1); 541 PetscLogStageRegister(str, &gamg_stages[fine_level]); 542 } 543 for (lidx=0,level=pc_gamg->m_Nlevels-1; 544 lidx<fine_level; 545 lidx++, level--){ 546 ierr = PCMGSetInterpolation( a_pc, lidx+1, Parr[level] );CHKERRQ(ierr); 547 if( !PETSC_TRUE ) { 548 PetscViewer viewer; char fname[32]; 549 sprintf(fname,"Pmat_%d.m",level); 550 ierr = PetscViewerASCIIOpen( wcomm, fname, &viewer ); CHKERRQ(ierr); 551 ierr = PetscViewerSetFormat( viewer, PETSC_VIEWER_ASCII_MATLAB); CHKERRQ(ierr); 552 ierr = MatView( Parr[level], viewer ); CHKERRQ(ierr); 553 ierr = PetscViewerDestroy( &viewer ); 554 } 555 ierr = MatDestroy( &Parr[level] ); CHKERRQ(ierr); 556 ierr = MatDestroy( &Aarr[level] ); CHKERRQ(ierr); 557 if( PETSC_FALSE ) { 558 char str[32]; 559 sprintf(str,"MG Level %d (%d)",lidx+1,level-1); 560 PetscLogStageRegister(str, &gamg_stages[level-1]); 561 } 562 } 563 564 /* setupcalled is set to 0 so that MG is setup from scratch */ 565 a_pc->setupcalled = 0; 566 ierr = PCSetUp_MG(a_pc);CHKERRQ(ierr); 567 PetscFunctionReturn(0); 568 } 569 570 /* ------------------------------------------------------------------------- */ 571 /* 572 PCDestroy_GAMG - Destroys the private context for the GAMG preconditioner 573 that was created with PCCreate_GAMG(). 574 575 Input Parameter: 576 . pc - the preconditioner context 577 578 Application Interface Routine: PCDestroy() 579 */ 580 #undef __FUNCT__ 581 #define __FUNCT__ "PCDestroy_GAMG" 582 PetscErrorCode PCDestroy_GAMG(PC pc) 583 { 584 PetscErrorCode ierr; 585 PC_MG *mg = (PC_MG*)pc->data; 586 PC_GAMG *pc_gamg= (PC_GAMG*)mg->innerctx; 587 588 PetscFunctionBegin; 589 ierr = PCReset_GAMG(pc);CHKERRQ(ierr); 590 ierr = PetscFree(pc_gamg);CHKERRQ(ierr); 591 ierr = PCDestroy_MG(pc);CHKERRQ(ierr); 592 PetscFunctionReturn(0); 593 } 594 595 #undef __FUNCT__ 596 #define __FUNCT__ "PCSetFromOptions_GAMG" 597 PetscErrorCode PCSetFromOptions_GAMG(PC pc) 598 { 599 /* PetscErrorCode ierr; */ 600 /* PC_MG *mg = (PC_MG*)pc->data; */ 601 /* PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; */ 602 /* MPI_Comm comm = ((PetscObject)pc)->comm; */ 603 604 PetscFunctionBegin; 605 PetscFunctionReturn(0); 606 } 607 608 /* -------------------------------------------------------------------------- */ 609 /* 610 PCCreate_GAMG - Creates a GAMG preconditioner context, PC_GAMG 611 612 Input Parameter: 613 . pc - the preconditioner context 614 615 Application Interface Routine: PCCreate() 616 617 */ 618 /* MC 619 PCGAMG - Use algebraic multigrid preconditioning. This preconditioner requires you provide 620 fine grid discretization matrix and coordinates on the fine grid. 621 622 Options Database Key: 623 Multigrid options(inherited) 624 + -pc_mg_cycles <1>: 1 for V cycle, 2 for W-cycle (MGSetCycles) 625 . -pc_mg_smoothup <1>: Number of post-smoothing steps (MGSetNumberSmoothUp) 626 . -pc_mg_smoothdown <1>: Number of pre-smoothing steps (MGSetNumberSmoothDown) 627 -pc_mg_type <multiplicative>: (one of) additive multiplicative full cascade kascade 628 GAMG options: 629 630 Level: intermediate 631 Concepts: multigrid 632 633 .seealso: PCCreate(), PCSetType(), PCType (for list of available types), PC, PCMGType, 634 PCMGSetLevels(), PCMGGetLevels(), PCMGSetType(), MPSetCycles(), PCMGSetNumberSmoothDown(), 635 PCMGSetNumberSmoothUp(), PCMGGetCoarseSolve(), PCMGSetResidual(), PCMGSetInterpolation(), 636 PCMGSetRestriction(), PCMGGetSmoother(), PCMGGetSmootherUp(), PCMGGetSmootherDown(), 637 PCMGSetCyclesOnLevel(), PCMGSetRhs(), PCMGSetX(), PCMGSetR() 638 M */ 639 640 EXTERN_C_BEGIN 641 #undef __FUNCT__ 642 #define __FUNCT__ "PCCreate_GAMG" 643 PetscErrorCode PCCreate_GAMG(PC pc) 644 { 645 PetscErrorCode ierr; 646 PC_GAMG *pc_gamg; 647 PC_MG *mg; 648 PetscClassId cookie; 649 650 PetscFunctionBegin; 651 /* PCGAMG is an inherited class of PCMG. Initialize pc as PCMG */ 652 ierr = PCSetType(pc,PCMG);CHKERRQ(ierr); /* calls PCCreate_MG() and MGCreate_Private() */ 653 ierr = PetscObjectChangeTypeName((PetscObject)pc,PCGAMG);CHKERRQ(ierr); 654 655 /* create a supporting struct and attach it to pc */ 656 ierr = PetscNewLog(pc,PC_GAMG,&pc_gamg);CHKERRQ(ierr); 657 mg = (PC_MG*)pc->data; 658 mg->innerctx = pc_gamg; 659 660 pc_gamg->m_Nlevels = -1; 661 662 /* overwrite the pointers of PCMG by the functions of PCGAMG */ 663 pc->ops->setfromoptions = PCSetFromOptions_GAMG; 664 pc->ops->setup = PCSetUp_GAMG; 665 pc->ops->reset = PCReset_GAMG; 666 pc->ops->destroy = PCDestroy_GAMG; 667 668 ierr = PetscObjectComposeFunctionDynamic( (PetscObject)pc, 669 "PCSetCoordinates_C", 670 "PCSetCoordinates_GAMG", 671 PCSetCoordinates_GAMG);CHKERRQ(ierr); 672 673 PetscClassIdRegister("GAMG Setup",&cookie); 674 PetscLogEventRegister("GAMG-createProl", cookie, &gamg_setup_stages[SET1]); 675 PetscLogEventRegister("GAMG-partLevel", cookie, &gamg_setup_stages[SET2]); 676 PetscLogEventRegister("GAMG-MIS Graph", cookie, &gamg_setup_stages[SET3]); 677 PetscLogEventRegister("GAMG-MIS-Agg", cookie, &gamg_setup_stages[SET4]); 678 PetscLogEventRegister("GAMG-growSupp", cookie, &gamg_setup_stages[SET5]); 679 PetscLogEventRegister("GAMG-tri-Prol", cookie, &gamg_setup_stages[SET6]); 680 PetscLogEventRegister("GAMG-find-prol", cookie, &gamg_setup_stages[FIND_V]); 681 682 PetscFunctionReturn(0); 683 } 684 EXTERN_C_END 685