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 PetscInt m_data_rows; 14 PetscInt m_data_cols; 15 PetscBool m_useSA; 16 PetscReal *m_data; /* blocked vector of vertex data on fine grid (coordinates) */ 17 } PC_GAMG; 18 19 /* -------------------------------------------------------------------------- */ 20 /* 21 PCSetCoordinates_GAMG 22 23 Input Parameter: 24 . pc - the preconditioner context 25 */ 26 EXTERN_C_BEGIN 27 #undef __FUNCT__ 28 #define __FUNCT__ "PCSetCoordinates_GAMG" 29 PetscErrorCode PCSetCoordinates_GAMG( PC a_pc, PetscInt a_ndm, PetscReal *a_coords ) 30 { 31 PC_MG *mg = (PC_MG*)a_pc->data; 32 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 33 PetscErrorCode ierr; 34 PetscInt arrsz,bs,my0,kk,ii,jj,nloc,Iend; 35 Mat Amat = a_pc->pmat; 36 PetscBool flag; 37 char str[16]; 38 39 PetscFunctionBegin; 40 ierr = MatGetBlockSize( Amat, &bs ); CHKERRQ( ierr ); 41 ierr = MatGetOwnershipRange( Amat, &my0, &Iend ); CHKERRQ(ierr); 42 nloc = (Iend-my0)/bs; 43 if((Iend-my0)%bs!=0) SETERRQ1(((PetscObject)Amat)->comm,PETSC_ERR_ARG_WRONG, "Bad local size %d.",nloc); 44 45 ierr = PetscOptionsGetString(PETSC_NULL,"-pc_gamg_type",str,16,&flag); CHKERRQ( ierr ); 46 pc_gamg->m_useSA = (PetscBool)(flag && strcmp(str,"sa") == 0); 47 48 pc_gamg->m_data_rows = 1; 49 if(a_coords == 0) pc_gamg->m_useSA = PETSC_TRUE; /* use SA if no data */ 50 if( !pc_gamg->m_useSA ) pc_gamg->m_data_cols = a_ndm; /* coordinates */ 51 else{ /* SA: null space vectors */ 52 if(a_coords != 0 && bs==1 ) pc_gamg->m_data_cols = 1; /* scalar w/ coords and SA (not needed) */ 53 else if(a_coords != 0) pc_gamg->m_data_cols = (a_ndm==2 ? 3 : 6); /* elasticity */ 54 else pc_gamg->m_data_cols = bs; /* no data, force SA with constant null space vectors */ 55 pc_gamg->m_data_rows = bs; 56 } 57 arrsz = nloc*pc_gamg->m_data_rows*pc_gamg->m_data_cols; 58 59 /* create data - syntactic sugar that should be refactored at some point */ 60 if (!pc_gamg->m_data || (pc_gamg->m_data_sz != arrsz)) { 61 ierr = PetscFree( pc_gamg->m_data ); CHKERRQ(ierr); 62 ierr = PetscMalloc((arrsz+1)*sizeof(double), &pc_gamg->m_data ); CHKERRQ(ierr); 63 } 64 for(kk=0;kk<arrsz;kk++)pc_gamg->m_data[kk] = -999.; 65 pc_gamg->m_data[arrsz] = -99.; 66 /* copy data in - column oriented */ 67 if( pc_gamg->m_useSA ) { 68 const PetscInt M = Iend - my0; 69 for(kk=0;kk<nloc;kk++){ 70 PetscReal *data = &pc_gamg->m_data[kk*bs]; 71 if( pc_gamg->m_data_cols==1 ) *data = 1.0; 72 else { 73 for(ii=0;ii<bs;ii++) 74 for(jj=0;jj<bs;jj++) 75 if(ii==jj)data[ii*M + jj] = 1.0; /* translational modes */ 76 else data[ii*M + jj] = 0.0; 77 if( a_coords != 0 ) { 78 if( a_ndm == 2 ){ /* rotational modes */ 79 data += 2*M; 80 data[0] = -a_coords[2*kk+1]; 81 data[1] = a_coords[2*kk]; 82 } 83 else { 84 data += 3*M; 85 data[0] = 0.0; data[M+0] = a_coords[3*kk+2]; data[2*M+0] = -a_coords[3*kk+1]; 86 data[1] = -a_coords[3*kk+2]; data[M+1] = 0.0; data[2*M+1] = a_coords[3*kk]; 87 data[2] = a_coords[3*kk+1]; data[M+2] = -a_coords[3*kk]; data[2*M+2] = 0.0; 88 } 89 } 90 } 91 } 92 } 93 else { 94 for( kk = 0 ; kk < nloc ; kk++ ){ 95 for( ii = 0 ; ii < a_ndm ; ii++ ) { 96 pc_gamg->m_data[ii*nloc + kk] = a_coords[kk*a_ndm + ii]; 97 } 98 } 99 } 100 101 assert(pc_gamg->m_data[arrsz] == -99.); 102 for(kk=0;kk<arrsz;kk++) assert(pc_gamg->m_data[kk] != -999.); // debug 103 104 pc_gamg->m_data_sz = arrsz; 105 pc_gamg->m_dim = a_ndm; 106 107 PetscFunctionReturn(0); 108 } 109 EXTERN_C_END 110 111 112 /* -----------------------------------------------------------------------------*/ 113 #undef __FUNCT__ 114 #define __FUNCT__ "PCReset_GAMG" 115 PetscErrorCode PCReset_GAMG(PC pc) 116 { 117 PetscErrorCode ierr; 118 PC_MG *mg = (PC_MG*)pc->data; 119 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 120 121 PetscFunctionBegin; 122 ierr = PetscFree(pc_gamg->m_data);CHKERRQ(ierr); 123 pc_gamg->m_data = 0; pc_gamg->m_data_sz = 0; 124 PetscFunctionReturn(0); 125 } 126 127 /* -------------------------------------------------------------------------- */ 128 /* 129 partitionLevel 130 131 Input Parameter: 132 . a_Amat_fine - matrix on this fine (k) level 133 . a_ndata_rows - size of data to move (coarse grid) 134 . a_ndata_cols - size of data to move (coarse grid) 135 In/Output Parameter: 136 . a_P_inout - prolongation operator to the next level (k-1) 137 . a_coarse_data - data that need to be moved 138 . a_active_proc - number of active procs 139 Output Parameter: 140 . a_Amat_crs - coarse matrix that is created (k-1) 141 */ 142 143 #undef __FUNCT__ 144 #define __FUNCT__ "partitionLevel" 145 PetscErrorCode partitionLevel( Mat a_Amat_fine, 146 PetscInt a_ndata_rows, 147 PetscInt a_ndata_cols, 148 PetscInt a_cbs, 149 Mat *a_P_inout, 150 PetscReal **a_coarse_data, 151 PetscMPIInt *a_active_proc, 152 Mat *a_Amat_crs 153 ) 154 { 155 PetscErrorCode ierr; 156 Mat Cmat,Pnew,Pold=*a_P_inout; 157 IS new_indices,isnum; 158 MPI_Comm wcomm = ((PetscObject)a_Amat_fine)->comm; 159 PetscMPIInt nactive_procs,mype,npe; 160 PetscInt Istart,Iend,Istart0,Iend0,ncrs0,ncrs_new,fbs; 161 PetscInt neq,NN; 162 PetscMPIInt new_npe,targ_npe; 163 PetscBool flag = PETSC_FALSE; 164 165 PetscFunctionBegin; 166 ierr = MPI_Comm_rank( wcomm, &mype ); CHKERRQ(ierr); 167 ierr = MPI_Comm_size( wcomm, &npe ); CHKERRQ(ierr); 168 ierr = MatGetBlockSize( a_Amat_fine, &fbs ); CHKERRQ(ierr); 169 /* RAP */ 170 ierr = MatPtAP( a_Amat_fine, Pold, MAT_INITIAL_MATRIX, 2.0, &Cmat ); CHKERRQ(ierr); 171 172 ierr = MatSetBlockSize( Cmat, a_cbs ); CHKERRQ(ierr); 173 174 ierr = MatGetOwnershipRange( Cmat, &Istart0, &Iend0 ); CHKERRQ(ierr); 175 ncrs0 = (Iend0-Istart0)/a_cbs; assert((Iend0-Istart0)%a_cbs == 0); 176 177 /* Repartition Cmat_{k} and move colums of P^{k}_{k-1} and coordinates accordingly */ 178 ierr = MatGetSize( Cmat, &neq, &NN );CHKERRQ(ierr); 179 #define MIN_EQ_PROC 500 180 nactive_procs = *a_active_proc; 181 targ_npe = neq/MIN_EQ_PROC; /* hardwire min. number of eq/proc */ 182 #define TOP_GRID_LIM 500 183 if( targ_npe == 0 || neq < TOP_GRID_LIM ) new_npe = 1; /* chop coarsest grid */ 184 else if (targ_npe >= nactive_procs ) new_npe = nactive_procs; /* no change */ 185 else { 186 PetscMPIInt factstart,fact; 187 new_npe = -9999; 188 factstart = nactive_procs; 189 for(fact=factstart;fact>0;fact--){ /* try to find a better number of procs */ 190 if( nactive_procs%fact==0 && neq/(nactive_procs/fact) > MIN_EQ_PROC ) { 191 new_npe = nactive_procs/fact; 192 } 193 } 194 if(new_npe == -9999) new_npe = nactive_procs; 195 } 196 197 ierr = PetscOptionsHasName(PETSC_NULL,"-pc_gamg_avoid_repartitioning",&flag); 198 CHKERRQ( ierr ); 199 if( !flag ) { /* re-partition */ 200 MatPartitioning mpart; 201 Mat adj; 202 const PetscInt *is_idx; 203 PetscInt is_sz,kk,jj,ii,old_fact=(npe/nactive_procs), *isnewproc_idx; 204 /* create sub communicator */ 205 MPI_Comm cm,new_comm; 206 PetscInt membershipKey = mype%old_fact, new_fact=(npe/new_npe),counts[npe]; 207 IS isnewproc; 208 209 *a_active_proc = new_npe; /* output for next level */ 210 ierr = MPI_Comm_split(wcomm, membershipKey, mype, &cm); CHKERRQ(ierr); 211 ierr = PetscCommDuplicate( cm, &new_comm, PETSC_NULL ); CHKERRQ(ierr); 212 ierr = MPI_Comm_free( &cm ); CHKERRQ(ierr); 213 214 /* MatPartitioningApply call MatConvert, which is collective */ 215 ierr = PetscLogEventBegin(gamg_setup_stages[SET12],0,0,0,0);CHKERRQ(ierr); 216 if( a_cbs==1) { 217 ierr = MatConvert( Cmat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj ); CHKERRQ(ierr); 218 } 219 else { 220 /* make a scalar matrix to partition */ 221 Mat tMat; 222 PetscInt Ii,ncols; const PetscScalar *vals; const PetscInt *idx; 223 MatInfo info; 224 ierr = MatGetInfo(Cmat,MAT_LOCAL,&info); CHKERRQ(ierr); 225 ncols = (PetscInt)info.nz_used/((ncrs0+1)*a_cbs*a_cbs)+1; 226 227 ierr = MatCreateMPIAIJ( wcomm, ncrs0, ncrs0, 228 PETSC_DETERMINE, PETSC_DETERMINE, 229 2*ncols, PETSC_NULL, ncols, PETSC_NULL, 230 &tMat ); 231 CHKERRQ(ierr); 232 233 for ( Ii = Istart0; Ii < Iend0; Ii++ ) { 234 PetscInt dest_row = Ii/a_cbs; 235 ierr = MatGetRow(Cmat,Ii,&ncols,&idx,&vals); CHKERRQ(ierr); 236 for( jj = 0 ; jj < ncols ; jj++ ){ 237 PetscInt dest_col = idx[jj]/a_cbs; 238 PetscScalar v = 1.0; 239 ierr = MatSetValues(tMat,1,&dest_row,1,&dest_col,&v,ADD_VALUES); CHKERRQ(ierr); 240 } 241 ierr = MatRestoreRow(Cmat,Ii,&ncols,&idx,&vals); CHKERRQ(ierr); 242 } 243 ierr = MatAssemblyBegin(tMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 244 ierr = MatAssemblyEnd(tMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 245 246 ierr = MatConvert( tMat, MATMPIADJ, MAT_INITIAL_MATRIX, &adj ); CHKERRQ(ierr); 247 248 ierr = MatDestroy( &tMat ); CHKERRQ(ierr); 249 } 250 if( membershipKey == 0 ) { 251 if(ncrs0==0)SETERRQ(PETSC_COMM_SELF,PETSC_ERR_LIB,"zero local nodes -- increase min"); 252 /* hack to fix global data that pmetis.c uses in 'adj' */ 253 for( kk=0 , jj=0 ; kk<=npe ; jj++, kk += old_fact ) { 254 adj->rmap->range[jj] = adj->rmap->range[kk]; 255 } 256 ierr = MatPartitioningCreate( new_comm, &mpart ); CHKERRQ(ierr); 257 ierr = MatPartitioningSetAdjacency( mpart, adj ); CHKERRQ(ierr); 258 ierr = MatPartitioningSetFromOptions( mpart ); CHKERRQ(ierr); 259 ierr = MatPartitioningSetNParts( mpart, new_npe ); CHKERRQ(ierr); 260 ierr = MatPartitioningApply( mpart, &isnewproc ); CHKERRQ(ierr); 261 ierr = MatPartitioningDestroy( &mpart ); CHKERRQ(ierr); 262 /* collect IS info */ 263 ierr = ISGetLocalSize( isnewproc, &is_sz ); CHKERRQ(ierr); 264 ierr = PetscMalloc( a_cbs*is_sz*sizeof(PetscInt), &isnewproc_idx ); CHKERRQ(ierr); 265 ierr = ISGetIndices( isnewproc, &is_idx ); CHKERRQ(ierr); 266 /* spread partitioning across machine - probably the right thing to do but machine spec. */ 267 for(kk=0,jj=0;kk<is_sz;kk++){ 268 for(ii=0 ; ii<a_cbs ; ii++, jj++ ) { /* expand for equation level by 'bs' */ 269 isnewproc_idx[jj] = is_idx[kk] * new_fact; 270 } 271 } 272 ierr = ISRestoreIndices( isnewproc, &is_idx ); CHKERRQ(ierr); 273 ierr = ISDestroy( &isnewproc ); CHKERRQ(ierr); 274 is_sz *= a_cbs; 275 } 276 else { 277 isnewproc_idx = 0; 278 is_sz = 0; 279 } 280 ierr = MatDestroy( &adj ); CHKERRQ(ierr); 281 ierr = MPI_Comm_free( &new_comm ); CHKERRQ(ierr); 282 ierr = ISCreateGeneral( wcomm, is_sz, isnewproc_idx, PETSC_COPY_VALUES, &isnewproc ); 283 if( membershipKey == 0 ) { 284 ierr = PetscFree( isnewproc_idx ); CHKERRQ(ierr); 285 } 286 287 /* 288 Create an index set from the isnewproc index set to indicate the mapping TO 289 */ 290 ierr = ISPartitioningToNumbering( isnewproc, &isnum ); CHKERRQ(ierr); 291 /* 292 Determine how many elements are assigned to each processor 293 */ 294 ierr = ISPartitioningCount( isnewproc, npe, counts ); CHKERRQ(ierr); 295 ierr = ISDestroy( &isnewproc ); CHKERRQ(ierr); 296 ncrs_new = counts[mype]/a_cbs; 297 ierr = PetscLogEventEnd(gamg_setup_stages[SET12],0,0,0,0); CHKERRQ(ierr); 298 299 { /* Create a vector to contain the newly ordered element information */ 300 const PetscInt *idx, data_sz=a_ndata_rows*a_ndata_cols; 301 const PetscInt stride0=ncrs0*a_ndata_rows,strideNew=ncrs_new*a_ndata_rows; 302 PetscInt ii,jj,kk; 303 IS isscat; 304 PetscScalar *array; 305 Vec src_crd, dest_crd; 306 PetscReal *data = *a_coarse_data; 307 VecScatter vecscat; 308 PetscInt tidx[ncrs0*data_sz]; 309 310 ierr = VecCreate( wcomm, &dest_crd ); 311 ierr = VecSetSizes( dest_crd, data_sz*ncrs_new, PETSC_DECIDE ); CHKERRQ(ierr); 312 ierr = VecSetFromOptions( dest_crd ); CHKERRQ(ierr); /*funny vector-get global options?*/ 313 /* 314 There are 'a_ndata_rows*a_ndata_cols' data items per node, (one can think of the vectors of having 315 a block size of ...). Note, ISs are expanded into equation space by 'a_cbs'. 316 */ 317 ierr = ISGetIndices( isnum, &idx ); CHKERRQ(ierr); 318 for(ii=0,jj=0; ii<ncrs0 ; ii++) { 319 PetscInt id = idx[ii*a_cbs]/a_cbs; /* get node back */ 320 for( kk=0; kk<data_sz ; kk++, jj++) tidx[jj] = id*data_sz + kk; 321 } 322 ierr = ISRestoreIndices( isnum, &idx ); CHKERRQ(ierr); 323 ierr = ISCreateGeneral( wcomm, data_sz*ncrs0, tidx, PETSC_COPY_VALUES, &isscat ); 324 CHKERRQ(ierr); 325 /* 326 Create a vector to contain the original vertex information for each element 327 */ 328 ierr = VecCreateSeq( PETSC_COMM_SELF, data_sz*ncrs0, &src_crd ); CHKERRQ(ierr); 329 for( jj=0; jj<a_ndata_cols ; jj++ ) { 330 for( ii=0 ; ii<ncrs0 ; ii++) { 331 for( kk=0; kk<a_ndata_rows ; kk++ ) { 332 PetscInt ix = ii*a_ndata_rows + kk + jj*stride0, jx = ii*data_sz + kk*a_ndata_cols + jj; 333 ierr = VecSetValues( src_crd, 1, &jx, &data[ix], INSERT_VALUES ); CHKERRQ(ierr); 334 } 335 } 336 } 337 ierr = VecAssemblyBegin(src_crd); CHKERRQ(ierr); 338 ierr = VecAssemblyEnd(src_crd); CHKERRQ(ierr); 339 /* 340 Scatter the element vertex information (still in the original vertex ordering) 341 to the correct processor 342 */ 343 ierr = VecScatterCreate( src_crd, PETSC_NULL, dest_crd, isscat, &vecscat); 344 CHKERRQ(ierr); 345 ierr = ISDestroy( &isscat ); CHKERRQ(ierr); 346 ierr = VecScatterBegin(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 347 ierr = VecScatterEnd(vecscat,src_crd,dest_crd,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 348 ierr = VecScatterDestroy( &vecscat ); CHKERRQ(ierr); 349 ierr = VecDestroy( &src_crd ); CHKERRQ(ierr); 350 /* 351 Put the element vertex data into a new allocation of the gdata->ele 352 */ 353 ierr = PetscFree( *a_coarse_data ); CHKERRQ(ierr); 354 ierr = PetscMalloc( data_sz*ncrs_new*sizeof(PetscReal), a_coarse_data ); CHKERRQ(ierr); 355 356 ierr = VecGetArray( dest_crd, &array ); CHKERRQ(ierr); 357 data = *a_coarse_data; 358 for( jj=0; jj<a_ndata_cols ; jj++ ) { 359 for( ii=0 ; ii<ncrs_new ; ii++) { 360 for( kk=0; kk<a_ndata_rows ; kk++ ) { 361 PetscInt ix = ii*a_ndata_rows + kk + jj*strideNew, jx = ii*data_sz + kk*a_ndata_cols + jj; 362 data[ix] = PetscRealPart(array[jx]); 363 array[jx] = 1.e300; 364 } 365 } 366 } 367 ierr = VecRestoreArray( dest_crd, &array ); CHKERRQ(ierr); 368 ierr = VecDestroy( &dest_crd ); CHKERRQ(ierr); 369 } 370 371 /* 372 Invert for MatGetSubMatrix 373 */ 374 ierr = ISInvertPermutation( isnum, ncrs_new*a_cbs, &new_indices ); CHKERRQ(ierr); 375 ierr = ISSort( new_indices ); CHKERRQ(ierr); /* is this needed? */ 376 ierr = ISDestroy( &isnum ); CHKERRQ(ierr); 377 /* A_crs output */ 378 ierr = MatGetSubMatrix( Cmat, new_indices, new_indices, MAT_INITIAL_MATRIX, a_Amat_crs ); 379 CHKERRQ(ierr); 380 381 ierr = MatDestroy( &Cmat ); CHKERRQ(ierr); 382 Cmat = *a_Amat_crs; /* output */ 383 ierr = MatSetBlockSize( Cmat, a_cbs ); CHKERRQ(ierr); 384 385 /* prolongator */ 386 ierr = MatGetOwnershipRange( Pold, &Istart, &Iend ); CHKERRQ(ierr); 387 { 388 IS findices; 389 ierr = ISCreateStride(wcomm,Iend-Istart,Istart,1,&findices); CHKERRQ(ierr); 390 ierr = MatGetSubMatrix( Pold, findices, new_indices, MAT_INITIAL_MATRIX, &Pnew ); 391 CHKERRQ(ierr); 392 ierr = ISDestroy( &findices ); CHKERRQ(ierr); 393 } 394 ierr = MatDestroy( a_P_inout ); CHKERRQ(ierr); 395 *a_P_inout = Pnew; /* output */ 396 ierr = ISDestroy( &new_indices ); CHKERRQ(ierr); 397 } 398 else { 399 *a_Amat_crs = Cmat; /* output */ 400 } 401 402 PetscFunctionReturn(0); 403 } 404 405 #define GAMG_MAXLEVELS 30 406 #if defined(PETSC_USE_LOG) 407 PetscLogStage gamg_stages[20]; 408 #endif 409 /* -------------------------------------------------------------------------- */ 410 /* 411 PCSetUp_GAMG - Prepares for the use of the GAMG preconditioner 412 by setting data structures and options. 413 414 Input Parameter: 415 . pc - the preconditioner context 416 417 Application Interface Routine: PCSetUp() 418 419 Notes: 420 The interface routine PCSetUp() is not usually called directly by 421 the user, but instead is called by PCApply() if necessary. 422 */ 423 #undef __FUNCT__ 424 #define __FUNCT__ "PCSetUp_GAMG" 425 PetscErrorCode PCSetUp_GAMG( PC a_pc ) 426 { 427 PetscErrorCode ierr; 428 PC_MG *mg = (PC_MG*)a_pc->data; 429 PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; 430 Mat Amat = a_pc->mat, Pmat = a_pc->pmat; 431 PetscInt fine_level, level, level1, M, N, bs, nloc, lidx, Istart, Iend; 432 MPI_Comm wcomm = ((PetscObject)a_pc)->comm; 433 PetscMPIInt mype,npe,nactivepe; 434 PetscBool isOK; 435 Mat Aarr[GAMG_MAXLEVELS], Parr[GAMG_MAXLEVELS]; 436 PetscReal *coarse_data = 0, *data, emaxs[GAMG_MAXLEVELS]; 437 MatInfo info; 438 439 PetscFunctionBegin; 440 if( a_pc->setupcalled ) { 441 /* no state data in GAMG to destroy */ 442 ierr = PCReset_MG( a_pc ); CHKERRQ(ierr); 443 } 444 ierr = MPI_Comm_rank(wcomm,&mype);CHKERRQ(ierr); 445 ierr = MPI_Comm_size(wcomm,&npe);CHKERRQ(ierr); 446 /* GAMG requires input of fine-grid matrix. It determines nlevels. */ 447 ierr = MatGetBlockSize( Amat, &bs ); CHKERRQ(ierr); 448 ierr = MatGetSize( Amat, &M, &N );CHKERRQ(ierr); 449 ierr = MatGetOwnershipRange( Amat, &Istart, &Iend ); CHKERRQ(ierr); 450 nloc = (Iend-Istart)/bs; assert((Iend-Istart)%bs == 0); 451 452 /* get data of not around */ 453 if( pc_gamg->m_data == 0 && nloc > 0 ) { 454 ierr = PCSetCoordinates_GAMG( a_pc, -1, 0 ); CHKERRQ( ierr ); 455 } 456 data = pc_gamg->m_data; 457 458 /* Get A_i and R_i */ 459 ierr = MatGetInfo(Amat,MAT_GLOBAL_SUM,&info); CHKERRQ(ierr); 460 PetscPrintf(PETSC_COMM_WORLD,"\t[%d]%s level %d N=%d, n data rows=%d, n data cols=%d, nnz/row (ave)=%d, np=%d\n", 461 mype,__FUNCT__,0,N,pc_gamg->m_data_rows,pc_gamg->m_data_cols,(PetscInt)info.nz_used/N,npe); 462 for ( level=0, Aarr[0] = Pmat, nactivepe = npe; /* hard wired stopping logic */ 463 level < GAMG_MAXLEVELS-1 && (level==0 || M/bs>TOP_GRID_LIM) && (npe==1 || nactivepe>1); 464 level++ ){ 465 level1 = level + 1; 466 ierr = PetscLogEventBegin(gamg_setup_stages[SET1],0,0,0,0);CHKERRQ(ierr); 467 ierr = createProlongation(Aarr[level], data, pc_gamg->m_dim, pc_gamg->m_data_cols, pc_gamg->m_useSA, 468 &bs, &Parr[level1], &coarse_data, &isOK, &emaxs[level] ); 469 CHKERRQ(ierr); 470 ierr = PetscFree( data ); CHKERRQ( ierr ); 471 ierr = PetscLogEventEnd(gamg_setup_stages[SET1],0,0,0,0);CHKERRQ(ierr); 472 473 if(level==0) Aarr[0] = Amat; /* use Pmat for finest level setup, but use mat for solver */ 474 475 if( isOK ) { 476 ierr = PetscLogEventBegin(gamg_setup_stages[SET2],0,0,0,0);CHKERRQ(ierr); 477 ierr = partitionLevel( Aarr[level], pc_gamg->m_useSA ? bs : 1, pc_gamg->m_data_cols, bs, 478 &Parr[level1], &coarse_data, &nactivepe, &Aarr[level1] ); 479 CHKERRQ(ierr); 480 ierr = PetscLogEventEnd(gamg_setup_stages[SET2],0,0,0,0);CHKERRQ(ierr); 481 ierr = MatGetSize( Aarr[level1], &M, &N );CHKERRQ(ierr); 482 ierr = MatGetInfo(Aarr[level1],MAT_GLOBAL_SUM,&info); CHKERRQ(ierr); 483 PetscPrintf(PETSC_COMM_WORLD,"\t\t[%d]%s %d) N=%d, bs=%d, n data cols=%d, nnz/row (ave)=%d, %d active pes\n", 484 mype,__FUNCT__,level1,N,bs,pc_gamg->m_data_cols,(PetscInt)info.nz_used/N,nactivepe); 485 /* coarse grids with SA can have zero row/cols from singleton aggregates */ 486 /* aggregation method can probably gaurrentee this does not happen! - be safe for now */ 487 488 if( PETSC_TRUE ){ 489 Vec diag; PetscScalar *data_arr,v; PetscInt Istart,Iend,kk,nloc,id; 490 ierr = MatGetOwnershipRange(Aarr[level1], &Istart, &Iend); CHKERRQ(ierr); 491 nloc = Iend-Istart; 492 ierr = MatGetVecs( Aarr[level1], &diag, 0 ); CHKERRQ(ierr); 493 ierr = MatGetDiagonal( Aarr[level1], diag ); CHKERRQ(ierr); 494 ierr = VecGetArray( diag, &data_arr ); CHKERRQ(ierr); 495 for(kk=0;kk<nloc;kk++){ 496 if(data_arr[kk]==0.0) { 497 id = kk + Istart; v = 1.e-1; 498 ierr = MatSetValues(Aarr[level1],1,&id,1,&id,&v,INSERT_VALUES); 499 CHKERRQ(ierr); 500 /* PetscPrintf(PETSC_COMM_SELF,"[%d]%s warning: added diag to zero (%d) on level %d \n",mype,__FUNCT__,id,level); */ 501 } 502 } 503 ierr = VecRestoreArray( diag, &data_arr ); CHKERRQ(ierr); 504 ierr = VecDestroy( &diag ); CHKERRQ(ierr); 505 ierr = MatAssemblyBegin(Aarr[level1],MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 506 ierr = MatAssemblyEnd(Aarr[level1],MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 507 } 508 } 509 else{ 510 break; 511 } 512 data = coarse_data; 513 } 514 ierr = PetscFree( coarse_data ); CHKERRQ( ierr ); 515 PetscPrintf(PETSC_COMM_WORLD,"\t[%d]%s %d levels\n",0,__FUNCT__,level + 1); 516 pc_gamg->m_data = 0; /* destroyed coordinate data */ 517 pc_gamg->m_Nlevels = level + 1; 518 fine_level = level; 519 ierr = PCMGSetLevels(a_pc,pc_gamg->m_Nlevels,PETSC_NULL);CHKERRQ(ierr); 520 521 /* set default smoothers */ 522 for ( lidx=1, level = pc_gamg->m_Nlevels-2; 523 lidx <= fine_level; 524 lidx++, level--) { 525 PetscReal emax, emin; 526 KSP smoother; PC subpc; 527 ierr = PCMGGetSmoother( a_pc, lidx, &smoother ); CHKERRQ(ierr); 528 ierr = KSPSetType( smoother, KSPCHEBYCHEV );CHKERRQ(ierr); 529 if( emaxs[level] > 0.0 ) emax = emaxs[level]; 530 else{ /* eigen estimate 'emax' */ 531 KSP eksp; Mat Lmat = Aarr[level]; 532 Vec bb, xx; PC pc; 533 534 ierr = MatGetVecs( Lmat, &bb, 0 ); CHKERRQ(ierr); 535 ierr = MatGetVecs( Lmat, &xx, 0 ); CHKERRQ(ierr); 536 { 537 PetscRandom rctx; 538 ierr = PetscRandomCreate(wcomm,&rctx);CHKERRQ(ierr); 539 ierr = PetscRandomSetFromOptions(rctx);CHKERRQ(ierr); 540 ierr = VecSetRandom(bb,rctx);CHKERRQ(ierr); 541 ierr = PetscRandomDestroy( &rctx ); CHKERRQ(ierr); 542 } 543 ierr = KSPCreate(wcomm,&eksp);CHKERRQ(ierr); 544 ierr = KSPSetType( eksp, KSPCG ); CHKERRQ(ierr); 545 ierr = KSPSetInitialGuessNonzero( eksp, PETSC_FALSE ); CHKERRQ(ierr); 546 ierr = KSPSetOperators( eksp, Lmat, Lmat, DIFFERENT_NONZERO_PATTERN ); CHKERRQ( ierr ); 547 ierr = KSPGetPC( eksp, &pc );CHKERRQ( ierr ); 548 ierr = PCSetType( pc, PETSC_GAMG_SMOOTHER ); CHKERRQ(ierr); /* should be same as above */ 549 ierr = KSPSetTolerances( eksp, PETSC_DEFAULT, PETSC_DEFAULT, PETSC_DEFAULT, 10 ); 550 CHKERRQ(ierr); 551 //ierr = KSPSetConvergenceTest( eksp, KSPSkipConverged, 0, 0 ); CHKERRQ(ierr); 552 ierr = KSPSetNormType( eksp, KSP_NORM_NONE ); CHKERRQ(ierr); 553 554 ierr = KSPSetComputeSingularValues( eksp,PETSC_TRUE ); CHKERRQ(ierr); 555 ierr = KSPSolve( eksp, bb, xx ); CHKERRQ(ierr); 556 ierr = KSPComputeExtremeSingularValues( eksp, &emax, &emin ); CHKERRQ(ierr); 557 ierr = VecDestroy( &xx ); CHKERRQ(ierr); 558 ierr = VecDestroy( &bb ); CHKERRQ(ierr); 559 ierr = KSPDestroy( &eksp ); CHKERRQ(ierr); 560 PetscPrintf(PETSC_COMM_WORLD,"%s max eigen = %e min = %e\n",__FUNCT__,emax,emin); 561 } 562 { 563 PetscInt N1, N0, tt; 564 ierr = MatGetSize( Aarr[level], &N1, &tt ); CHKERRQ(ierr); 565 ierr = MatGetSize( Aarr[level+1], &N0, &tt ); CHKERRQ(ierr); 566 emin = .5*emax/((PetscReal)N1/(PetscReal)N0); /* this should be about the coarsening rate */ 567 emax *= 1.05; 568 } 569 570 ierr = KSPSetOperators( smoother, Aarr[level], Aarr[level], DIFFERENT_NONZERO_PATTERN ); 571 ierr = KSPChebychevSetEigenvalues( smoother, emax, emin );CHKERRQ(ierr); 572 ierr = KSPSetTolerances(smoother,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,2); CHKERRQ(ierr); 573 ierr = KSPGetPC( smoother, &subpc ); CHKERRQ(ierr); 574 ierr = PCSetType( subpc, PETSC_GAMG_SMOOTHER ); CHKERRQ(ierr); 575 ierr = KSPSetNormType( smoother, KSP_NORM_NONE ); CHKERRQ(ierr); 576 } 577 { 578 KSP smoother; /* coarse grid */ 579 Mat Lmat = Aarr[pc_gamg->m_Nlevels-1]; 580 ierr = PCMGGetSmoother( a_pc, 0, &smoother ); CHKERRQ(ierr); 581 ierr = KSPSetOperators( smoother, Lmat, Lmat, DIFFERENT_NONZERO_PATTERN ); 582 CHKERRQ(ierr); 583 ierr = KSPSetNormType( smoother, KSP_NORM_NONE ); CHKERRQ(ierr); 584 } 585 586 /* should be called in PCSetFromOptions_GAMG(), but cannot be called prior to PCMGSetLevels() */ 587 ierr = PCSetFromOptions_MG(a_pc); CHKERRQ(ierr); 588 { 589 PetscBool galerkin; 590 ierr = PCMGGetGalerkin( a_pc, &galerkin); CHKERRQ(ierr); 591 if(galerkin){ 592 SETERRQ(wcomm,PETSC_ERR_ARG_WRONG, "GAMG does galerkin manually so it must not be used in PC_MG."); 593 } 594 } 595 596 /* set interpolation between the levels, create timer stages, clean up */ 597 if( PETSC_FALSE ) { 598 char str[32]; 599 sprintf(str,"MG Level %d (%d)",0,pc_gamg->m_Nlevels-1); 600 PetscLogStageRegister(str, &gamg_stages[fine_level]); 601 } 602 for (lidx=0,level=pc_gamg->m_Nlevels-1; 603 lidx<fine_level; 604 lidx++, level--){ 605 ierr = PCMGSetInterpolation( a_pc, lidx+1, Parr[level] );CHKERRQ(ierr); 606 if( !PETSC_TRUE ) { 607 PetscViewer viewer; char fname[32]; 608 sprintf(fname,"Pmat_%d.m",level); 609 ierr = PetscViewerASCIIOpen( wcomm, fname, &viewer ); CHKERRQ(ierr); 610 ierr = PetscViewerSetFormat( viewer, PETSC_VIEWER_ASCII_MATLAB); CHKERRQ(ierr); 611 ierr = MatView( Parr[level], viewer ); CHKERRQ(ierr); 612 ierr = PetscViewerDestroy( &viewer ); 613 sprintf(fname,"Amat_%d.m",level); 614 ierr = PetscViewerASCIIOpen( wcomm, fname, &viewer ); CHKERRQ(ierr); 615 ierr = PetscViewerSetFormat( viewer, PETSC_VIEWER_ASCII_MATLAB); CHKERRQ(ierr); 616 ierr = MatView( Aarr[level], viewer ); CHKERRQ(ierr); 617 ierr = PetscViewerDestroy( &viewer ); 618 } 619 ierr = MatDestroy( &Parr[level] ); CHKERRQ(ierr); 620 ierr = MatDestroy( &Aarr[level] ); CHKERRQ(ierr); 621 if( PETSC_FALSE ) { 622 char str[32]; 623 sprintf(str,"MG Level %d (%d)",lidx+1,level-1); 624 PetscLogStageRegister(str, &gamg_stages[level-1]); 625 } 626 } 627 628 /* setupcalled is set to 0 so that MG is setup from scratch */ 629 a_pc->setupcalled = 0; 630 ierr = PCSetUp_MG(a_pc);CHKERRQ(ierr); 631 632 PetscFunctionReturn(0); 633 } 634 635 /* ------------------------------------------------------------------------- */ 636 /* 637 PCDestroy_GAMG - Destroys the private context for the GAMG preconditioner 638 that was created with PCCreate_GAMG(). 639 640 Input Parameter: 641 . pc - the preconditioner context 642 643 Application Interface Routine: PCDestroy() 644 */ 645 #undef __FUNCT__ 646 #define __FUNCT__ "PCDestroy_GAMG" 647 PetscErrorCode PCDestroy_GAMG(PC pc) 648 { 649 PetscErrorCode ierr; 650 PC_MG *mg = (PC_MG*)pc->data; 651 PC_GAMG *pc_gamg= (PC_GAMG*)mg->innerctx; 652 653 PetscFunctionBegin; 654 ierr = PCReset_GAMG(pc);CHKERRQ(ierr); 655 ierr = PetscFree(pc_gamg);CHKERRQ(ierr); 656 ierr = PCDestroy_MG(pc);CHKERRQ(ierr); 657 PetscFunctionReturn(0); 658 } 659 660 #undef __FUNCT__ 661 #define __FUNCT__ "PCSetFromOptions_GAMG" 662 PetscErrorCode PCSetFromOptions_GAMG(PC pc) 663 { 664 /* PetscErrorCode ierr; */ 665 /* PC_MG *mg = (PC_MG*)pc->data; */ 666 /* PC_GAMG *pc_gamg = (PC_GAMG*)mg->innerctx; */ 667 /* MPI_Comm comm = ((PetscObject)pc)->comm; */ 668 669 PetscFunctionBegin; 670 PetscFunctionReturn(0); 671 } 672 673 /* -------------------------------------------------------------------------- */ 674 /* 675 PCCreate_GAMG - Creates a GAMG preconditioner context, PC_GAMG 676 677 Input Parameter: 678 . pc - the preconditioner context 679 680 Application Interface Routine: PCCreate() 681 682 */ 683 /* MC 684 PCGAMG - Use algebraic multigrid preconditioning. This preconditioner requires you provide 685 fine grid discretization matrix and coordinates on the fine grid. 686 687 Options Database Key: 688 Multigrid options(inherited) 689 + -pc_mg_cycles <1>: 1 for V cycle, 2 for W-cycle (MGSetCycles) 690 . -pc_mg_smoothup <1>: Number of post-smoothing steps (MGSetNumberSmoothUp) 691 . -pc_mg_smoothdown <1>: Number of pre-smoothing steps (MGSetNumberSmoothDown) 692 -pc_mg_type <multiplicative>: (one of) additive multiplicative full cascade kascade 693 GAMG options: 694 695 Level: intermediate 696 Concepts: multigrid 697 698 .seealso: PCCreate(), PCSetType(), PCType (for list of available types), PC, PCMGType, 699 PCMGSetLevels(), PCMGGetLevels(), PCMGSetType(), MPSetCycles(), PCMGSetNumberSmoothDown(), 700 PCMGSetNumberSmoothUp(), PCMGGetCoarseSolve(), PCMGSetResidual(), PCMGSetInterpolation(), 701 PCMGSetRestriction(), PCMGGetSmoother(), PCMGGetSmootherUp(), PCMGGetSmootherDown(), 702 PCMGSetCyclesOnLevel(), PCMGSetRhs(), PCMGSetX(), PCMGSetR() 703 M */ 704 705 EXTERN_C_BEGIN 706 #undef __FUNCT__ 707 #define __FUNCT__ "PCCreate_GAMG" 708 PetscErrorCode PCCreate_GAMG(PC pc) 709 { 710 PetscErrorCode ierr; 711 PC_GAMG *pc_gamg; 712 PC_MG *mg; 713 PetscClassId cookie; 714 715 PetscFunctionBegin; 716 /* PCGAMG is an inherited class of PCMG. Initialize pc as PCMG */ 717 ierr = PCSetType(pc,PCMG);CHKERRQ(ierr); /* calls PCCreate_MG() and MGCreate_Private() */ 718 ierr = PetscObjectChangeTypeName((PetscObject)pc,PCGAMG);CHKERRQ(ierr); 719 720 /* create a supporting struct and attach it to pc */ 721 ierr = PetscNewLog(pc,PC_GAMG,&pc_gamg);CHKERRQ(ierr); 722 mg = (PC_MG*)pc->data; 723 mg->innerctx = pc_gamg; 724 725 pc_gamg->m_Nlevels = -1; 726 727 /* overwrite the pointers of PCMG by the functions of PCGAMG */ 728 pc->ops->setfromoptions = PCSetFromOptions_GAMG; 729 pc->ops->setup = PCSetUp_GAMG; 730 pc->ops->reset = PCReset_GAMG; 731 pc->ops->destroy = PCDestroy_GAMG; 732 733 ierr = PetscObjectComposeFunctionDynamic( (PetscObject)pc, 734 "PCSetCoordinates_C", 735 "PCSetCoordinates_GAMG", 736 PCSetCoordinates_GAMG);CHKERRQ(ierr); 737 738 PetscClassIdRegister("GAMG Setup",&cookie); 739 PetscLogEventRegister("GAMG: createProl", cookie, &gamg_setup_stages[SET1]); 740 PetscLogEventRegister(" make graph", cookie, &gamg_setup_stages[SET3]); 741 PetscLogEventRegister(" MIS/Agg", cookie, &gamg_setup_stages[SET4]); 742 PetscLogEventRegister(" geo: growSupp", cookie, &gamg_setup_stages[SET5]); 743 PetscLogEventRegister(" geo: triangle", cookie, &gamg_setup_stages[SET6]); 744 PetscLogEventRegister(" search & set", cookie, &gamg_setup_stages[FIND_V]); 745 PetscLogEventRegister(" SA: init", cookie, &gamg_setup_stages[SET7]); 746 /* PetscLogEventRegister(" SA: frmProl0", cookie, &gamg_setup_stages[SET8]); */ 747 PetscLogEventRegister(" SA: smooth", cookie, &gamg_setup_stages[SET9]); 748 PetscLogEventRegister("GAMG: partLevel", cookie, &gamg_setup_stages[SET2]); 749 PetscLogEventRegister(" PL repartition", cookie, &gamg_setup_stages[SET12]); 750 /* PetscLogEventRegister(" PL move data", cookie, &gamg_setup_stages[SET13]); */ 751 /* PetscLogEventRegister("GAMG: fix", cookie, &gamg_setup_stages[SET10]); */ 752 /* PetscLogEventRegister("GAMG: set levels", cookie, &gamg_setup_stages[SET11]); */ 753 754 PetscFunctionReturn(0); 755 } 756 EXTERN_C_END 757