Actual source code: nasm.c

petsc-dev 2014-02-02
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  1: #include <petsc-private/snesimpl.h>             /*I   "petscsnes.h"   I*/
  2: #include <petscdm.h>

  4: typedef struct {
  5:   PetscInt   n;                   /* local subdomains */
  6:   SNES       *subsnes;            /* nonlinear solvers for each subdomain */
  7:   Vec        *x;                  /* solution vectors */
  8:   Vec        *xl;                 /* solution local vectors */
  9:   Vec        *y;                  /* step vectors */
 10:   Vec        *b;                  /* rhs vectors */
 11:   VecScatter *oscatter;           /* scatter from global space to the subdomain global space */
 12:   VecScatter *iscatter;           /* scatter from global space to the nonoverlapping subdomain space */
 13:   VecScatter *gscatter;           /* scatter from global space to the subdomain local space */
 14:   PCASMType  type;                /* ASM type */
 15:   PetscBool  usesdm;              /* use the DM for setting up the subproblems */
 16:   PetscBool  finaljacobian;       /* compute the jacobian of the converged solution */
 17:   PetscReal  damping;             /* damping parameter for updates from the blocks */
 18:   PetscBool  same_local_solves;   /* flag to determine if the solvers have been individually modified */

 20:   /* logging events */
 21:   PetscLogEvent eventrestrictinterp;
 22:   PetscLogEvent eventsubsolve;

 24:   PetscInt      fjtype;            /* type of computed jacobian */
 25:   Vec           xinit;             /* initial solution in case the final jacobian type is computed as first */
 26: } SNES_NASM;

 28: const char *const SNESNASMTypes[] = {"NONE","RESTRICT","INTERPOLATE","BASIC","PCASMType","PC_ASM_",0};
 29: const char *const SNESNASMFJTypes[] = {"FINALOUTER","FINALINNER","INITIAL"};

 33: PetscErrorCode SNESReset_NASM(SNES snes)
 34: {
 35:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
 37:   PetscInt       i;

 40:   for (i=0; i<nasm->n; i++) {
 41:     if (nasm->xl) { VecDestroy(&nasm->xl[i]); }
 42:     if (nasm->x) { VecDestroy(&nasm->x[i]); }
 43:     if (nasm->y) { VecDestroy(&nasm->y[i]); }
 44:     if (nasm->b) { VecDestroy(&nasm->b[i]); }

 46:     if (nasm->subsnes) { SNESDestroy(&nasm->subsnes[i]); }
 47:     if (nasm->oscatter) { VecScatterDestroy(&nasm->oscatter[i]); }
 48:     if (nasm->iscatter) { VecScatterDestroy(&nasm->iscatter[i]); }
 49:     if (nasm->gscatter) { VecScatterDestroy(&nasm->gscatter[i]); }
 50:   }

 52:   if (nasm->x) {PetscFree(nasm->x);}
 53:   if (nasm->xl) {PetscFree(nasm->xl);}
 54:   if (nasm->y) {PetscFree(nasm->y);}
 55:   if (nasm->b) {PetscFree(nasm->b);}

 57:   if (nasm->xinit) {VecDestroy(&nasm->xinit);}

 59:   if (nasm->subsnes) {PetscFree(nasm->subsnes);}
 60:   if (nasm->oscatter) {PetscFree(nasm->oscatter);}
 61:   if (nasm->iscatter) {PetscFree(nasm->iscatter);}
 62:   if (nasm->gscatter) {PetscFree(nasm->gscatter);}

 64:   nasm->eventrestrictinterp = 0;
 65:   nasm->eventsubsolve = 0;
 66:   return(0);
 67: }

 71: PetscErrorCode SNESDestroy_NASM(SNES snes)
 72: {

 76:   SNESReset_NASM(snes);
 77:   PetscFree(snes->data);
 78:   return(0);
 79: }

 83: PetscErrorCode DMGlobalToLocalSubDomainDirichletHook_Private(DM dm,Vec g,InsertMode mode,Vec l,void *ctx)
 84: {
 86:   Vec            bcs = (Vec)ctx;

 89:   VecCopy(bcs,l);
 90:   return(0);
 91: }

 95: PetscErrorCode SNESSetUp_NASM(SNES snes)
 96: {
 97:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
 99:   DM             dm,subdm;
100:   DM             *subdms;
101:   PetscInt       i;
102:   const char     *optionsprefix;
103:   Vec            F;
104:   PetscMPIInt    size;
105:   KSP            ksp;
106:   PC             pc;

109:   if (!nasm->subsnes) {
110:     SNESGetDM(snes,&dm);
111:     if (dm) {
112:       nasm->usesdm = PETSC_TRUE;
113:       DMCreateDomainDecomposition(dm,&nasm->n,NULL,NULL,NULL,&subdms);
114:       if (!subdms) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_ARG_WRONGSTATE,"DM has no default decomposition defined.  Set subsolves manually with SNESNASMSetSubdomains().");
115:       DMCreateDomainDecompositionScatters(dm,nasm->n,subdms,&nasm->iscatter,&nasm->oscatter,&nasm->gscatter);

117:       SNESGetOptionsPrefix(snes, &optionsprefix);
118:       PetscMalloc1(nasm->n,&nasm->subsnes);
119:       for (i=0; i<nasm->n; i++) {
120:         SNESCreate(PETSC_COMM_SELF,&nasm->subsnes[i]);
121:         SNESAppendOptionsPrefix(nasm->subsnes[i],optionsprefix);
122:         SNESAppendOptionsPrefix(nasm->subsnes[i],"sub_");
123:         SNESSetDM(nasm->subsnes[i],subdms[i]);
124:         MPI_Comm_size(PetscObjectComm((PetscObject)nasm->subsnes[i]),&size);
125:         if (size == 1) {
126:           SNESGetKSP(nasm->subsnes[i],&ksp);
127:           KSPGetPC(ksp,&pc);
128:           KSPSetType(ksp,KSPPREONLY);
129:           PCSetType(pc,PCLU);
130:         }
131:         SNESSetFromOptions(nasm->subsnes[i]);
132:         DMDestroy(&subdms[i]);
133:       }
134:       PetscFree(subdms);
135:     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Cannot construct local problems automatically without a DM!");
136:   } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Must set subproblems manually if there is no DM!");
137:   /* allocate the global vectors */
138:   if (!nasm->x) {
139:     PetscCalloc1(nasm->n,&nasm->x);
140:   }
141:   if (!nasm->xl) {
142:     PetscCalloc1(nasm->n,&nasm->xl);
143:   }
144:   if (!nasm->y) {
145:     PetscCalloc1(nasm->n,&nasm->y);
146:   }
147:   if (!nasm->b) {
148:     PetscCalloc1(nasm->n,&nasm->b);
149:   }

151:   for (i=0; i<nasm->n; i++) {
152:     SNESGetFunction(nasm->subsnes[i],&F,NULL,NULL);
153:     if (!nasm->x[i]) {VecDuplicate(F,&nasm->x[i]);}
154:     if (!nasm->y[i]) {VecDuplicate(F,&nasm->y[i]);}
155:     if (!nasm->b[i]) {VecDuplicate(F,&nasm->b[i]);}
156:     if (!nasm->xl[i]) {
157:       SNESGetDM(nasm->subsnes[i],&subdm);
158:       DMCreateLocalVector(subdm,&nasm->xl[i]);
159:     }
160:     DMGlobalToLocalHookAdd(subdm,DMGlobalToLocalSubDomainDirichletHook_Private,NULL,nasm->xl[i]);
161:   }
162:   if (nasm->finaljacobian) {
163:     SNESSetUpMatrices(snes);
164:     if (nasm->fjtype == 2) {
165:       VecDuplicate(snes->vec_sol,&nasm->xinit);
166:     }
167:     for (i=0; i<nasm->n;i++) {
168:       SNESSetUpMatrices(nasm->subsnes[i]);
169:     }
170:   }
171:   return(0);
172: }

176: PetscErrorCode SNESSetFromOptions_NASM(SNES snes)
177: {
178:   PetscErrorCode    ierr;
179:   PCASMType         asmtype;
180:   PetscBool         flg,monflg,subviewflg;
181:   SNES_NASM         *nasm = (SNES_NASM*)snes->data;

184:   PetscOptionsHead("Nonlinear Additive Schwartz options");
185:   PetscOptionsEnum("-snes_nasm_type","Type of restriction/extension","",SNESNASMTypes,(PetscEnum)nasm->type,(PetscEnum*)&asmtype,&flg);
186:   if (flg) nasm->type = asmtype;
187:   flg    = PETSC_FALSE;
188:   monflg = PETSC_TRUE;
189:   PetscOptionsReal("-snes_nasm_damping","Log times for subSNES solves and restriction","SNESNASMSetDamping",nasm->damping,&nasm->damping,&flg);
190:   if (flg) {SNESNASMSetDamping(snes,nasm->damping);}
191:   subviewflg = PETSC_FALSE;
192:   PetscOptionsBool("-snes_nasm_sub_view","Print detailed information for every processor when using -snes_view","",subviewflg,&subviewflg,&flg);
193:   if (flg) {
194:     nasm->same_local_solves = PETSC_FALSE;
195:     if (!subviewflg) {
196:       nasm->same_local_solves = PETSC_TRUE;
197:     }
198:   }
199:   PetscOptionsBool("-snes_nasm_finaljacobian","Compute the global jacobian of the final iterate (for ASPIN)","",nasm->finaljacobian,&nasm->finaljacobian,NULL);
200:   PetscOptionsEList("-snes_nasm_finaljacobian_type","The type of the final jacobian computed.","",SNESNASMFJTypes,3,SNESNASMFJTypes[0],&nasm->fjtype,NULL);
201:   PetscOptionsBool("-snes_nasm_log","Log times for subSNES solves and restriction","",monflg,&monflg,&flg);
202:   if (flg) {
203:     PetscLogEventRegister("SNESNASMSubSolve",((PetscObject)snes)->classid,&nasm->eventsubsolve);
204:     PetscLogEventRegister("SNESNASMRestrict",((PetscObject)snes)->classid,&nasm->eventrestrictinterp);
205:   }
206:   PetscOptionsTail();
207:   return(0);
208: }

212: PetscErrorCode SNESView_NASM(SNES snes, PetscViewer viewer)
213: {
214:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
216:   PetscMPIInt    rank,size;
217:   PetscInt       i,N,bsz;
218:   PetscBool      iascii,isstring;
219:   PetscViewer    sviewer;
220:   MPI_Comm       comm;

223:   PetscObjectGetComm((PetscObject)snes,&comm);
224:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
225:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);
226:   MPI_Comm_rank(comm,&rank);
227:   MPI_Comm_size(comm,&size);
228:   MPI_Allreduce(&nasm->n,&N,1,MPIU_INT,MPI_SUM,comm);
229:   if (iascii) {
230:     PetscViewerASCIIPrintf(viewer, "  Nonlinear Additive Schwarz: total subdomain blocks = %D\n",N);
231:     if (nasm->same_local_solves) {
232:       if (nasm->subsnes) {
233:         PetscViewerASCIIPrintf(viewer,"  Local solve is the same for all blocks:\n");
234:         PetscViewerASCIIPushTab(viewer);
235:         PetscViewerGetSingleton(viewer,&sviewer);
236:         if (!rank) {
237:           PetscViewerASCIIPushTab(viewer);
238:           SNESView(nasm->subsnes[0],sviewer);
239:           PetscViewerASCIIPopTab(viewer);
240:         }
241:         PetscViewerRestoreSingleton(viewer,&sviewer);
242:         PetscViewerASCIIPopTab(viewer);
243:       }
244:     } else {
245:       /* print the solver on each block */
246:       PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);
247:       PetscViewerASCIISynchronizedPrintf(viewer,"  [%d] number of local blocks = %D\n",(int)rank,nasm->n);
248:       PetscViewerFlush(viewer);
249:       PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);
250:       PetscViewerASCIIPrintf(viewer,"  Local solve info for each block is in the following SNES objects:\n");
251:       PetscViewerASCIIPushTab(viewer);
252:       PetscViewerASCIIPrintf(viewer,"- - - - - - - - - - - - - - - - - -\n");
253:       PetscViewerGetSingleton(viewer,&sviewer);
254:       for (i=0; i<nasm->n; i++) {
255:         VecGetLocalSize(nasm->x[i],&bsz);
256:         PetscViewerASCIIPrintf(sviewer,"[%d] local block number %D, size = %D\n",(int)rank,i,bsz);
257:         SNESView(nasm->subsnes[i],sviewer);
258:         PetscViewerASCIIPrintf(sviewer,"- - - - - - - - - - - - - - - - - -\n");
259:       }
260:       PetscViewerRestoreSingleton(viewer,&sviewer);
261:       PetscViewerFlush(viewer);
262:       PetscViewerASCIIPopTab(viewer);
263:     }
264:   } else if (isstring) {
265:     PetscViewerStringSPrintf(viewer," blocks=%D,type=%s",N,SNESNASMTypes[nasm->type]);
266:     PetscViewerGetSingleton(viewer,&sviewer);
267:     if (nasm->subsnes && !rank) {SNESView(nasm->subsnes[0],sviewer);}
268:     PetscViewerRestoreSingleton(viewer,&sviewer);
269:   }
270:   return(0);
271: }

275: /*@
276:    SNESNASMSetSubdomains - Manually Set the context required to restrict and solve subdomain problems.

278:    Not Collective

280:    Input Parameters:
281: +  SNES - the SNES context
282: .  n - the number of local subdomains
283: .  subsnes - solvers defined on the local subdomains
284: .  iscatter - scatters into the nonoverlapping portions of the local subdomains
285: .  oscatter - scatters into the overlapping portions of the local subdomains
286: -  gscatter - scatters into the (ghosted) local vector of the local subdomain

288:    Level: intermediate

290: .keywords: SNES, NASM

292: .seealso: SNESNASM, SNESNASMGetSubdomains()
293: @*/
294: PetscErrorCode SNESNASMSetSubdomains(SNES snes,PetscInt n,SNES subsnes[],VecScatter iscatter[],VecScatter oscatter[],VecScatter gscatter[])
295: {
297:   PetscErrorCode (*f)(SNES,PetscInt,SNES*,VecScatter*,VecScatter*,VecScatter*);

300:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMSetSubdomains_C",&f);
301:   if (f) {(f)(snes,n,subsnes,iscatter,oscatter,gscatter);}
302:   return(0);
303: }

307: PetscErrorCode SNESNASMSetSubdomains_NASM(SNES snes,PetscInt n,SNES subsnes[],VecScatter iscatter[],VecScatter oscatter[],VecScatter gscatter[])
308: {
309:   PetscInt       i;
311:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

314:   if (snes->setupcalled) SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"SNESNASMSetSubdomains() should be called before calling SNESSetUp().");

316:   /* tear down the previously set things */
317:   SNESReset(snes);

319:   nasm->n = n;
320:   if (oscatter) {
321:     for (i=0; i<n; i++) {PetscObjectReference((PetscObject)oscatter[i]);}
322:   }
323:   if (iscatter) {
324:     for (i=0; i<n; i++) {PetscObjectReference((PetscObject)iscatter[i]);}
325:   }
326:   if (gscatter) {
327:     for (i=0; i<n; i++) {PetscObjectReference((PetscObject)gscatter[i]);}
328:   }
329:   if (oscatter) {
330:     PetscMalloc1(n,&nasm->oscatter);
331:     for (i=0; i<n; i++) {
332:       nasm->oscatter[i] = oscatter[i];
333:     }
334:   }
335:   if (iscatter) {
336:     PetscMalloc1(n,&nasm->iscatter);
337:     for (i=0; i<n; i++) {
338:       nasm->iscatter[i] = iscatter[i];
339:     }
340:   }
341:   if (gscatter) {
342:     PetscMalloc1(n,&nasm->gscatter);
343:     for (i=0; i<n; i++) {
344:       nasm->gscatter[i] = gscatter[i];
345:     }
346:   }

348:   if (subsnes) {
349:     PetscMalloc1(n,&nasm->subsnes);
350:     for (i=0; i<n; i++) {
351:       nasm->subsnes[i] = subsnes[i];
352:     }
353:     nasm->same_local_solves = PETSC_FALSE;
354:   }
355:   return(0);
356: }

360: /*@
361:    SNESNASMGetSubdomains - Get the local subdomain context.

363:    Not Collective

365:    Input Parameters:
366: .  SNES - the SNES context

368:    Output Parameters:
369: +  n - the number of local subdomains
370: .  subsnes - solvers defined on the local subdomains
371: .  iscatter - scatters into the nonoverlapping portions of the local subdomains
372: .  oscatter - scatters into the overlapping portions of the local subdomains
373: -  gscatter - scatters into the (ghosted) local vector of the local subdomain

375:    Level: intermediate

377: .keywords: SNES, NASM

379: .seealso: SNESNASM, SNESNASMSetSubdomains()
380: @*/
381: PetscErrorCode SNESNASMGetSubdomains(SNES snes,PetscInt *n,SNES *subsnes[],VecScatter *iscatter[],VecScatter *oscatter[],VecScatter *gscatter[])
382: {
384:   PetscErrorCode (*f)(SNES,PetscInt*,SNES**,VecScatter**,VecScatter**,VecScatter**);

387:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMGetSubdomains_C",&f);
388:   if (f) {(f)(snes,n,subsnes,iscatter,oscatter,gscatter);}
389:   return(0);
390: }

394: PetscErrorCode SNESNASMGetSubdomains_NASM(SNES snes,PetscInt *n,SNES *subsnes[],VecScatter *iscatter[],VecScatter *oscatter[],VecScatter *gscatter[])
395: {
396:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

399:   if (n) *n = nasm->n;
400:   if (oscatter) *oscatter = nasm->oscatter;
401:   if (iscatter) *iscatter = nasm->iscatter;
402:   if (gscatter) *gscatter = nasm->gscatter;
403:   if (subsnes)  {
404:     *subsnes  = nasm->subsnes;
405:     nasm->same_local_solves = PETSC_FALSE;
406:   }
407:   return(0);
408: }

412: /*@
413:    SNESNASMGetSubdomainVecs - Get the processor-local subdomain vectors

415:    Not Collective

417:    Input Parameters:
418: .  SNES - the SNES context

420:    Output Parameters:
421: +  n - the number of local subdomains
422: .  x - The subdomain solution vector
423: .  y - The subdomain step vector
424: .  b - The subdomain RHS vector
425: -  xl - The subdomain local vectors (ghosted)

427:    Level: developer

429: .keywords: SNES, NASM

431: .seealso: SNESNASM, SNESNASMGetSubdomains()
432: @*/
433: PetscErrorCode SNESNASMGetSubdomainVecs(SNES snes,PetscInt *n,Vec **x,Vec **y,Vec **b, Vec **xl)
434: {
436:   PetscErrorCode (*f)(SNES,PetscInt*,Vec**,Vec**,Vec**,Vec**);

439:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMGetSubdomainVecs_C",&f);
440:   if (f) {(f)(snes,n,x,y,b,xl);}
441:   return(0);
442: }

446: PetscErrorCode SNESNASMGetSubdomainVecs_NASM(SNES snes,PetscInt *n,Vec **x,Vec **y,Vec **b,Vec **xl)
447: {
448:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

451:   if (n)  *n  = nasm->n;
452:   if (x)  *x  = nasm->x;
453:   if (y)  *y  = nasm->y;
454:   if (b)  *b  = nasm->b;
455:   if (xl) *xl = nasm->xl;
456:   return(0);
457: }

461: /*@
462:    SNESNASMSetComputeFinalJacobian - Schedules the computation of the global and subdomain jacobians upon convergence

464:    Collective on SNES

466:    Input Parameters:
467: +  SNES - the SNES context
468: -  flg - indication of whether to compute the jacobians or not

470:    Level: developer

472:    Notes: This is used almost exclusively in the implementation of ASPIN, where the converged subdomain and global jacobian
473:    is needed at each linear iteration.

475: .keywords: SNES, NASM, ASPIN

477: .seealso: SNESNASM, SNESNASMGetSubdomains()
478: @*/
479: PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES snes,PetscBool flg)
480: {
481:   PetscErrorCode (*f)(SNES,PetscBool);

485:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMSetComputeFinalJacobian_C",&f);
486:   if (f) {(f)(snes,flg);}
487:   return(0);
488: }

492: PetscErrorCode SNESNASMSetComputeFinalJacobian_NASM(SNES snes,PetscBool flg)
493: {
494:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

497:   nasm->finaljacobian = flg;
498:   if (flg) snes->usesksp = PETSC_TRUE;
499:   return(0);
500: }

504: /*@
505:    SNESNASMSetDamping - Sets the update damping for NASM

507:    Logically collective on SNES

509:    Input Parameters:
510: +  SNES - the SNES context
511: -  dmp - damping

513:    Level: intermediate

515: .keywords: SNES, NASM, damping

517: .seealso: SNESNASM, SNESNASMGetDamping()
518: @*/
519: PetscErrorCode SNESNASMSetDamping(SNES snes,PetscReal dmp)
520: {
521:   PetscErrorCode (*f)(SNES,PetscReal);

525:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMSetDamping_C",(void (**)(void))&f);
526:   if (f) {(f)(snes,dmp);}
527:   return(0);
528: }

532: PetscErrorCode SNESNASMSetDamping_NASM(SNES snes,PetscReal dmp)
533: {
534:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

537:   nasm->damping = dmp;
538:   return(0);
539: }

543: /*@
544:    SNESNASMGetDamping - Gets the update damping for NASM

546:    Not Collective

548:    Input Parameters:
549: +  SNES - the SNES context
550: -  dmp - damping

552:    Level: intermediate

554: .keywords: SNES, NASM, damping

556: .seealso: SNESNASM, SNESNASMSetDamping()
557: @*/
558: PetscErrorCode SNESNASMGetDamping(SNES snes,PetscReal *dmp)
559: {
560:   PetscErrorCode (*f)(SNES,PetscReal*);

564:   PetscObjectQueryFunction((PetscObject)snes,"SNESNASMGetDamping_C",(void (**)(void))&f);
565:   if (f) {(f)(snes,dmp);}
566:   return(0);
567: }

571: PetscErrorCode SNESNASMGetDamping_NASM(SNES snes,PetscReal *dmp)
572: {
573:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;

576:   *dmp = nasm->damping;
577:   return(0);
578: }


583: PetscErrorCode SNESNASMSolveLocal_Private(SNES snes,Vec B,Vec Y,Vec X)
584: {
585:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
586:   SNES           subsnes;
587:   PetscInt       i;
588:   PetscReal      dmp;
590:   Vec            Xlloc,Xl,Bl,Yl;
591:   VecScatter     iscat,oscat,gscat;
592:   DM             dm,subdm;

595:   SNESGetDM(snes,&dm);
596:   SNESNASMGetDamping(snes,&dmp);
597:   VecSet(Y,0);
598:   if (nasm->eventrestrictinterp) {PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);}
599:   for (i=0; i<nasm->n; i++) {
600:     /* scatter the solution to the local solution */
601:     Xlloc = nasm->xl[i];
602:     gscat   = nasm->gscatter[i];
603:     oscat   = nasm->oscatter[i];
604:     VecScatterBegin(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);
605:     if (B) {
606:       /* scatter the RHS to the local RHS */
607:       Bl   = nasm->b[i];
608:       VecScatterBegin(oscat,B,Bl,INSERT_VALUES,SCATTER_FORWARD);
609:     }
610:   }
611:   if (nasm->eventrestrictinterp) {PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);}


614:   if (nasm->eventsubsolve) {PetscLogEventBegin(nasm->eventsubsolve,snes,0,0,0);}
615:   for (i=0; i<nasm->n; i++) {
616:     Xl    = nasm->x[i];
617:     Xlloc = nasm->xl[i];
618:     Yl    = nasm->y[i];
619:     subsnes = nasm->subsnes[i];
620:     SNESGetDM(subsnes,&subdm);
621:     iscat   = nasm->iscatter[i];
622:     oscat   = nasm->oscatter[i];
623:     gscat   = nasm->gscatter[i];
624:     VecScatterEnd(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);
625:     if (B) {
626:       Bl   = nasm->b[i];
627:       VecScatterEnd(oscat,B,Bl,INSERT_VALUES,SCATTER_FORWARD);
628:     } else Bl = NULL;
629:     DMSubDomainRestrict(dm,oscat,gscat,subdm);
630:     DMLocalToGlobalBegin(subdm,Xlloc,INSERT_VALUES,Xl);
631:     DMLocalToGlobalEnd(subdm,Xlloc,INSERT_VALUES,Xl);
632:     VecCopy(Xl,Yl);
633:     SNESSolve(subsnes,Bl,Xl);
634:     VecAYPX(Yl,-1.0,Xl);
635:     if (nasm->type == PC_ASM_BASIC) {
636:       VecScatterBegin(oscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);
637:     } else if (nasm->type == PC_ASM_RESTRICT) {
638:       VecScatterBegin(iscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);
639:     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Only basic and restrict types are supported for SNESNASM");
640:   }
641:   if (nasm->eventsubsolve) {PetscLogEventEnd(nasm->eventsubsolve,snes,0,0,0);}
642:   if (nasm->eventrestrictinterp) {PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);}
643:   for (i=0; i<nasm->n; i++) {
644:     Yl    = nasm->y[i];
645:     iscat   = nasm->iscatter[i];
646:     oscat   = nasm->oscatter[i];
647:     if (nasm->type == PC_ASM_BASIC) {
648:       VecScatterEnd(oscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);
649:     } else if (nasm->type == PC_ASM_RESTRICT) {
650:       VecScatterEnd(iscat,Yl,Y,ADD_VALUES,SCATTER_REVERSE);
651:     } else SETERRQ(PetscObjectComm((PetscObject)snes),PETSC_ERR_ARG_WRONGSTATE,"Only basic and restrict types are supported for SNESNASM");
652:   }
653:   if (nasm->eventrestrictinterp) {PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);}
654:   VecAXPY(X,dmp,Y);
655:   return(0);
656: }

660: PetscErrorCode SNESNASMComputeFinalJacobian_Private(SNES snes, Vec Xfinal)
661: {
662:   Vec            X = Xfinal;
663:   SNES_NASM      *nasm = (SNES_NASM*)snes->data;
664:   SNES           subsnes;
665:   PetscInt       i,lag = 1;
667:   Vec            Xlloc,Xl,Fl,F;
668:   VecScatter     oscat,gscat;
669:   DM             dm,subdm;
670:   MatStructure   flg = DIFFERENT_NONZERO_PATTERN;
672:   if (nasm->fjtype == 2) X = nasm->xinit;
673:   F = snes->vec_func;
674:   if (snes->normschedule == SNES_NORM_NONE) {SNESComputeFunction(snes,X,F);}
675:   SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);
676:   SNESGetDM(snes,&dm);
677:   if (nasm->eventrestrictinterp) {PetscLogEventBegin(nasm->eventrestrictinterp,snes,0,0,0);}
678:   if (nasm->fjtype != 1) {
679:     for (i=0; i<nasm->n; i++) {
680:       Xlloc = nasm->xl[i];
681:       gscat = nasm->gscatter[i];
682:       oscat = nasm->oscatter[i];
683:       VecScatterBegin(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);
684:     }
685:   }
686:   if (nasm->eventrestrictinterp) {PetscLogEventEnd(nasm->eventrestrictinterp,snes,0,0,0);}
687:   for (i=0; i<nasm->n; i++) {
688:     Fl      = nasm->subsnes[i]->vec_func;
689:     Xl      = nasm->x[i];
690:     Xlloc   = nasm->xl[i];
691:     subsnes = nasm->subsnes[i];
692:     oscat   = nasm->oscatter[i];
693:     gscat   = nasm->gscatter[i];
694:     if (nasm->fjtype != 1) {VecScatterEnd(gscat,X,Xlloc,INSERT_VALUES,SCATTER_FORWARD);}
695:     SNESGetDM(subsnes,&subdm);
696:     DMSubDomainRestrict(dm,oscat,gscat,subdm);
697:     if (nasm->fjtype != 1) {
698:       DMLocalToGlobalBegin(subdm,Xlloc,INSERT_VALUES,Xl);
699:       DMLocalToGlobalEnd(subdm,Xlloc,INSERT_VALUES,Xl);
700:     }
701:     if (subsnes->lagjacobian == -1)    subsnes->lagjacobian = -2;
702:     else if (subsnes->lagjacobian > 1) lag = subsnes->lagjacobian;
703:     SNESComputeFunction(subsnes,Xl,Fl);
704:     SNESComputeJacobian(subsnes,Xl,&subsnes->jacobian,&subsnes->jacobian_pre,&flg);
705:     if (lag > 1) subsnes->lagjacobian = lag;
706:     KSPSetOperators(subsnes->ksp,subsnes->jacobian,subsnes->jacobian_pre,flg);
707:   }
708:   return(0);
709: }

713: PetscErrorCode SNESSolve_NASM(SNES snes)
714: {
715:   Vec              F;
716:   Vec              X;
717:   Vec              B;
718:   Vec              Y;
719:   PetscInt         i;
720:   PetscReal        fnorm = 0.0;
721:   PetscErrorCode   ierr;
722:   SNESNormSchedule normschedule;
723:   SNES_NASM        *nasm = (SNES_NASM*)snes->data;

726:   X = snes->vec_sol;
727:   Y = snes->vec_sol_update;
728:   F = snes->vec_func;
729:   B = snes->vec_rhs;

731:   PetscObjectSAWsTakeAccess((PetscObject)snes);
732:   snes->iter   = 0;
733:   snes->norm   = 0.;
734:   PetscObjectSAWsGrantAccess((PetscObject)snes);
735:   snes->reason = SNES_CONVERGED_ITERATING;
736:   SNESGetNormSchedule(snes, &normschedule);
737:   if (normschedule == SNES_NORM_ALWAYS || normschedule == SNES_NORM_INITIAL_ONLY || normschedule == SNES_NORM_INITIAL_FINAL_ONLY) {
738:     /* compute the initial function and preconditioned update delX */
739:     if (!snes->vec_func_init_set) {
740:       SNESComputeFunction(snes,X,F);
741:       if (snes->domainerror) {
742:         snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
743:         return(0);
744:       }
745:     } else snes->vec_func_init_set = PETSC_FALSE;

747:     VecNorm(F, NORM_2, &fnorm); /* fnorm <- ||F||  */
748:     if (PetscIsInfOrNanReal(fnorm)) {
749:       snes->reason = SNES_DIVERGED_FNORM_NAN;
750:       return(0);
751:     }
752:     PetscObjectSAWsTakeAccess((PetscObject)snes);
753:     snes->iter = 0;
754:     snes->norm = fnorm;
755:     PetscObjectSAWsGrantAccess((PetscObject)snes);
756:     SNESLogConvergenceHistory(snes,snes->norm,0);
757:     SNESMonitor(snes,0,snes->norm);

759:     /* test convergence */
760:     (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);
761:     if (snes->reason) return(0);
762:   } else {
763:     PetscObjectSAWsGrantAccess((PetscObject)snes);
764:     SNESLogConvergenceHistory(snes,snes->norm,0);
765:     SNESMonitor(snes,0,snes->norm);
766:   }

768:   /* Call general purpose update function */
769:   if (snes->ops->update) {
770:     (*snes->ops->update)(snes, snes->iter);
771:   }
772:   /* copy the initial solution over for later */
773:   if (nasm->fjtype == 2) {VecCopy(X,nasm->xinit);}

775:   for (i = 0; i < snes->max_its; i++) {
776:     SNESNASMSolveLocal_Private(snes,B,Y,X);
777:     if (normschedule == SNES_NORM_ALWAYS || ((i == snes->max_its - 1) && (normschedule == SNES_NORM_INITIAL_FINAL_ONLY || normschedule == SNES_NORM_FINAL_ONLY))) {
778:       SNESComputeFunction(snes,X,F);
779:       if (snes->domainerror) {
780:         snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN;
781:         break;
782:       }
783:       VecNorm(F, NORM_2, &fnorm); /* fnorm <- ||F||  */
784:       if (PetscIsInfOrNanReal(fnorm)) {
785:         snes->reason = SNES_DIVERGED_FNORM_NAN;
786:         break;
787:       }
788:     }
789:     /* Monitor convergence */
790:     PetscObjectSAWsTakeAccess((PetscObject)snes);
791:     snes->iter = i+1;
792:     snes->norm = fnorm;
793:     PetscObjectSAWsGrantAccess((PetscObject)snes);
794:     SNESLogConvergenceHistory(snes,snes->norm,0);
795:     SNESMonitor(snes,snes->iter,snes->norm);
796:     /* Test for convergence */
797:     if (normschedule == SNES_NORM_ALWAYS) {(*snes->ops->converged)(snes,snes->iter,0.0,0.0,fnorm,&snes->reason,snes->cnvP);}
798:     if (snes->reason) break;
799:     /* Call general purpose update function */
800:     if (snes->ops->update) {(*snes->ops->update)(snes, snes->iter);}
801:   }
802:   if (nasm->finaljacobian) {SNESNASMComputeFinalJacobian_Private(snes,X);}
803:   if (normschedule == SNES_NORM_ALWAYS) {
804:     if (i == snes->max_its) {
805:       PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",snes->max_its);
806:       if (!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT;
807:     }
808:   } else if (!snes->reason) snes->reason = SNES_CONVERGED_ITS; /* NASM is meant to be used as a preconditioner */
809:   return(0);
810: }

812: /*MC
813:   SNESNASM - Nonlinear Additive Schwartz

815:    Options Database:
816: +  -snes_nasm_log - enable logging events for the communication and solve stages
817: .  -snes_nasm_type <basic,restrict> - type of subdomain update used
818: .  -snes_nasm_finaljacobian - compute the local and global jacobians of the final iterate
819: .  -snes_nasm_finaljacobian_type <finalinner,finalouter,initial> pick state the jacobian is calculated at
820: .  -sub_snes_ - options prefix of the subdomain nonlinear solves
821: .  -sub_ksp_ - options prefix of the subdomain Krylov solver
822: -  -sub_pc_ - options prefix of the subdomain preconditioner

824:    Level: advanced

826: .seealso: SNESCreate(), SNES, SNESSetType(), SNESType (for list of available types)
827: M*/

831: PETSC_EXTERN PetscErrorCode SNESCreate_NASM(SNES snes)
832: {
833:   SNES_NASM      *nasm;

837:   PetscNewLog(snes,&nasm);
838:   snes->data = (void*)nasm;

840:   nasm->n        = PETSC_DECIDE;
841:   nasm->subsnes  = 0;
842:   nasm->x        = 0;
843:   nasm->xl       = 0;
844:   nasm->y        = 0;
845:   nasm->b        = 0;
846:   nasm->oscatter = 0;
847:   nasm->iscatter = 0;
848:   nasm->gscatter = 0;
849:   nasm->damping  = 1.;

851:   nasm->type = PC_ASM_BASIC;
852:   nasm->finaljacobian = PETSC_FALSE;
853:   nasm->same_local_solves = PETSC_TRUE;

855:   snes->ops->destroy        = SNESDestroy_NASM;
856:   snes->ops->setup          = SNESSetUp_NASM;
857:   snes->ops->setfromoptions = SNESSetFromOptions_NASM;
858:   snes->ops->view           = SNESView_NASM;
859:   snes->ops->solve          = SNESSolve_NASM;
860:   snes->ops->reset          = SNESReset_NASM;

862:   snes->usesksp = PETSC_FALSE;
863:   snes->usespc  = PETSC_FALSE;

865:   nasm->fjtype              = 0;
866:   nasm->xinit               = NULL;
867:   nasm->eventrestrictinterp = 0;
868:   nasm->eventsubsolve       = 0;

870:   if (!snes->tolerancesset) {
871:     snes->max_its   = 10000;
872:     snes->max_funcs = 10000;
873:   }

875:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMSetSubdomains_C",SNESNASMSetSubdomains_NASM);
876:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMGetSubdomains_C",SNESNASMGetSubdomains_NASM);
877:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMSetDamping_C",SNESNASMSetDamping_NASM);
878:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMGetDamping_C",SNESNASMGetDamping_NASM);
879:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMGetSubdomainVecs_C",SNESNASMGetSubdomainVecs_NASM);
880:   PetscObjectComposeFunction((PetscObject)snes,"SNESNASMSetComputeFinalJacobian_C",SNESNASMSetComputeFinalJacobian_NASM);
881:   return(0);
882: }