Actual source code: aomemscalable.c

petsc-3.4.5 2014-06-29
  2: /*
  3:     The memory scalable AO application ordering routines. These store the
  4:   local orderings on each processor.
  5: */

  7: #include <../src/vec/is/ao/aoimpl.h>          /*I  "petscao.h"   I*/

  9: typedef struct {
 10:   PetscInt    *app_loc;    /* app_loc[i] is the partner for the ith local PETSc slot */
 11:   PetscInt    *petsc_loc;  /* petsc_loc[j] is the partner for the jth local app slot */
 12:   PetscLayout map;         /* determines the local sizes of ao */
 13: } AO_MemoryScalable;

 15: /*
 16:        All processors have the same data so processor 1 prints it
 17: */
 20: PetscErrorCode AOView_MemoryScalable(AO ao,PetscViewer viewer)
 21: {
 22:   PetscErrorCode    ierr;
 23:   PetscMPIInt       rank,size;
 24:   AO_MemoryScalable *aomems = (AO_MemoryScalable*)ao->data;
 25:   PetscBool         iascii;
 26:   PetscMPIInt       tag_app,tag_petsc;
 27:   PetscLayout       map = aomems->map;
 28:   PetscInt          *app,*app_loc,*petsc,*petsc_loc,len,i,j;
 29:   MPI_Status        status;

 32:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
 33:   if (!iascii) SETERRQ1(PetscObjectComm((PetscObject)viewer),PETSC_ERR_SUP,"Viewer type %s not supported for AO MemoryScalable",((PetscObject)viewer)->type_name);

 35:   MPI_Comm_rank(PetscObjectComm((PetscObject)ao),&rank);
 36:   MPI_Comm_size(PetscObjectComm((PetscObject)ao),&size);

 38:   PetscObjectGetNewTag((PetscObject)ao,&tag_app);
 39:   PetscObjectGetNewTag((PetscObject)ao,&tag_petsc);

 41:   if (!rank) {
 42:     PetscViewerASCIIPrintf(viewer,"Number of elements in ordering %D\n",ao->N);
 43:     PetscViewerASCIIPrintf(viewer,  "PETSc->App  App->PETSc\n");

 45:     PetscMalloc2(map->N,PetscInt,&app,map->N,PetscInt,&petsc);
 46:     len  = map->n;
 47:     /* print local AO */
 48:     PetscViewerASCIIPrintf(viewer,"Process [%D]\n",rank);
 49:     for (i=0; i<len; i++) {
 50:       PetscViewerASCIIPrintf(viewer,"%3D  %3D    %3D  %3D\n",i,aomems->app_loc[i],i,aomems->petsc_loc[i]);
 51:     }

 53:     /* recv and print off-processor's AO */
 54:     for (i=1; i<size; i++) {
 55:       len       = map->range[i+1] - map->range[i];
 56:       app_loc   = app  + map->range[i];
 57:       petsc_loc = petsc+ map->range[i];
 58:       MPI_Recv(app_loc,(PetscMPIInt)len,MPIU_INT,i,tag_app,PetscObjectComm((PetscObject)ao),&status);
 59:       MPI_Recv(petsc_loc,(PetscMPIInt)len,MPIU_INT,i,tag_petsc,PetscObjectComm((PetscObject)ao),&status);
 60:       PetscViewerASCIIPrintf(viewer,"Process [%D]\n",i);
 61:       for (j=0; j<len; j++) {
 62:         PetscViewerASCIIPrintf(viewer,"%3D  %3D    %3D  %3D\n",map->range[i]+j,app_loc[j],map->range[i]+j,petsc_loc[j]);
 63:       }
 64:     }
 65:     PetscFree2(app,petsc);

 67:   } else {
 68:     /* send values */
 69:     MPI_Send((void*)aomems->app_loc,map->n,MPIU_INT,0,tag_app,PetscObjectComm((PetscObject)ao));
 70:     MPI_Send((void*)aomems->petsc_loc,map->n,MPIU_INT,0,tag_petsc,PetscObjectComm((PetscObject)ao));
 71:   }
 72:   PetscViewerFlush(viewer);
 73:   return(0);
 74: }

 78: PetscErrorCode AODestroy_MemoryScalable(AO ao)
 79: {
 80:   AO_MemoryScalable *aomems = (AO_MemoryScalable*)ao->data;
 81:   PetscErrorCode    ierr;

 84:   PetscFree2(aomems->app_loc,aomems->petsc_loc);
 85:   PetscLayoutDestroy(&aomems->map);
 86:   PetscFree(aomems);
 87:   return(0);
 88: }

 90: /*
 91:    Input Parameters:
 92: +   ao - the application ordering context
 93: .   n  - the number of integers in ia[]
 94: .   ia - the integers; these are replaced with their mapped value
 95: -   maploc - app_loc or petsc_loc in struct "AO_MemoryScalable"

 97:    Output Parameter:
 98: .   ia - the mapped interges
 99:  */
102: PetscErrorCode AOMap_MemoryScalable_private(AO ao,PetscInt n,PetscInt *ia,PetscInt *maploc)
103: {
104:   PetscErrorCode    ierr;
105:   AO_MemoryScalable *aomems = (AO_MemoryScalable*)ao->data;
106:   MPI_Comm          comm;
107:   PetscMPIInt       rank,size,tag1,tag2;
108:   PetscInt          *owner,*start,*nprocs,nsends,nreceives;
109:   PetscInt          nmax,count,*sindices,*rindices,i,j,idx,lastidx,*sindices2,*rindices2;
110:   PetscInt          *owners = aomems->map->range;
111:   MPI_Request       *send_waits,*recv_waits,*send_waits2,*recv_waits2;
112:   MPI_Status        recv_status;
113:   PetscMPIInt       nindices,source,widx;
114:   PetscInt          *rbuf,*sbuf;
115:   MPI_Status        *send_status,*send_status2;

118:   PetscObjectGetComm((PetscObject)ao,&comm);
119:   MPI_Comm_rank(comm,&rank);
120:   MPI_Comm_size(comm,&size);

122:   /*  first count number of contributors to each processor */
123:   PetscMalloc2(2*size,PetscInt,&nprocs,size,PetscInt,&start);
124:   PetscMemzero(nprocs,2*size*sizeof(PetscInt));
125:   PetscMalloc(n*sizeof(PetscInt),&owner);
126:   PetscMemzero(owner,n*sizeof(PetscInt));

128:   j       = 0;
129:   lastidx = -1;
130:   for (i=0; i<n; i++) {
131:     /* if indices are NOT locally sorted, need to start search at the beginning */
132:     if (lastidx > (idx = ia[i])) j = 0;
133:     lastidx = idx;
134:     for (; j<size; j++) {
135:       if (idx >= owners[j] && idx < owners[j+1]) {
136:         nprocs[2*j]++;     /* num of indices to be sent */
137:         nprocs[2*j+1] = 1; /* send to proc[j] */
138:         owner[i]      = j;
139:         break;
140:       }
141:     }
142:   }
143:   nprocs[2*rank]=nprocs[2*rank+1]=0; /* do not receive from self! */
144:   nsends        = 0;
145:   for (i=0; i<size; i++) nsends += nprocs[2*i+1];

147:   /* inform other processors of number of messages and max length*/
148:   PetscMaxSum(comm,nprocs,&nmax,&nreceives);

150:   /* allocate arrays */
151:   PetscObjectGetNewTag((PetscObject)ao,&tag1);
152:   PetscObjectGetNewTag((PetscObject)ao,&tag2);

154:   PetscMalloc2(nreceives*nmax,PetscInt,&rindices,nreceives,MPI_Request,&recv_waits);
155:   PetscMalloc2(nsends*nmax,PetscInt,&rindices2,nsends,MPI_Request,&recv_waits2);

157:   PetscMalloc3(n,PetscInt,&sindices,nsends,MPI_Request,&send_waits,nsends,MPI_Status,&send_status);
158:   PetscMalloc3(n,PetscInt,&sindices2,nreceives,MPI_Request,&send_waits2,nreceives,MPI_Status,&send_status2);

160:   /* post 1st receives: receive others requests
161:      since we don't know how long each individual message is we
162:      allocate the largest needed buffer for each receive. Potentially
163:      this is a lot of wasted space.
164:   */
165:   for (i=0,count=0; i<nreceives; i++) {
166:     MPI_Irecv(rindices+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,recv_waits+count++);
167:   }

169:   /* do 1st sends:
170:       1) starts[i] gives the starting index in svalues for stuff going to
171:          the ith processor
172:   */
173:   start[0] = 0;
174:   for (i=1; i<size; i++) start[i] = start[i-1] + nprocs[2*i-2];
175:   for (i=0; i<n; i++) {
176:     j = owner[i];
177:     if (j != rank) {
178:       sindices[start[j]++]  = ia[i];
179:     } else { /* compute my own map */
180:       if (ia[i] >= owners[rank] && ia[i] < owners[rank+1]) {
181:         ia[i] = maploc[ia[i]-owners[rank]];
182:       } else {
183:         ia[i] = -1;  /* ia[i] is not in the range of 0 and N-1, maps it to -1 */
184:       }
185:     }
186:   }

188:   start[0] = 0;
189:   for (i=1; i<size; i++) start[i] = start[i-1] + nprocs[2*i-2];
190:   for (i=0,count=0; i<size; i++) {
191:     if (nprocs[2*i+1]) {
192:       /* send my request to others */
193:       MPI_Isend(sindices+start[i],nprocs[2*i],MPIU_INT,i,tag1,comm,send_waits+count);
194:       /* post receive for the answer of my request */
195:       MPI_Irecv(sindices2+start[i],nprocs[2*i],MPIU_INT,i,tag2,comm,recv_waits2+count);
196:       count++;
197:     }
198:   }
199:   if (nsends != count) SETERRQ2(comm,PETSC_ERR_SUP,"nsends %d != count %d",nsends,count);

201:   /* wait on 1st sends */
202:   if (nsends) {
203:     MPI_Waitall(nsends,send_waits,send_status);
204:   }

206:   /* 1st recvs: other's requests */
207:   for (j=0; j< nreceives; j++) {
208:     MPI_Waitany(nreceives,recv_waits,&widx,&recv_status); /* idx: index of handle for operation that completed */
209:     MPI_Get_count(&recv_status,MPIU_INT,&nindices);
210:     rbuf   = rindices+nmax*widx; /* global index */
211:     source = recv_status.MPI_SOURCE;

213:     /* compute mapping */
214:     sbuf = rbuf;
215:     for (i=0; i<nindices; i++) sbuf[i] = maploc[rbuf[i]-owners[rank]];

217:     /* send mapping back to the sender */
218:     MPI_Isend(sbuf,nindices,MPIU_INT,source,tag2,comm,send_waits2+widx);
219:   }

221:   /* wait on 2nd sends */
222:   if (nreceives) {
223:     MPI_Waitall(nreceives,send_waits2,send_status2);
224:   }

226:   /* 2nd recvs: for the answer of my request */
227:   for (j=0; j< nsends; j++) {
228:     MPI_Waitany(nsends,recv_waits2,&widx,&recv_status);
229:     MPI_Get_count(&recv_status,MPIU_INT,&nindices);
230:     source = recv_status.MPI_SOURCE;
231:     /* pack output ia[] */
232:     rbuf  = sindices2+start[source];
233:     count = 0;
234:     for (i=0; i<n; i++) {
235:       if (source == owner[i]) ia[i] = rbuf[count++];
236:     }
237:   }

239:   /* free arrays */
240:   PetscFree2(nprocs,start);
241:   PetscFree(owner);
242:   PetscFree2(rindices,recv_waits);
243:   PetscFree2(rindices2,recv_waits2);
244:   PetscFree3(sindices,send_waits,send_status);
245:   PetscFree3(sindices2,send_waits2,send_status2);
246:   return(0);
247: }

251: PetscErrorCode AOPetscToApplication_MemoryScalable(AO ao,PetscInt n,PetscInt *ia)
252: {
253:   PetscErrorCode    ierr;
254:   AO_MemoryScalable *aomems  = (AO_MemoryScalable*)ao->data;
255:   PetscInt          *app_loc = aomems->app_loc;

258:   AOMap_MemoryScalable_private(ao,n,ia,app_loc);
259:   return(0);
260: }

264: PetscErrorCode AOApplicationToPetsc_MemoryScalable(AO ao,PetscInt n,PetscInt *ia)
265: {
266:   PetscErrorCode    ierr;
267:   AO_MemoryScalable *aomems    = (AO_MemoryScalable*)ao->data;
268:   PetscInt          *petsc_loc = aomems->petsc_loc;

271:   AOMap_MemoryScalable_private(ao,n,ia,petsc_loc);
272:   return(0);
273: }

275: static struct _AOOps AOOps_MemoryScalable = {
276:   AOView_MemoryScalable,
277:   AODestroy_MemoryScalable,
278:   AOPetscToApplication_MemoryScalable,
279:   AOApplicationToPetsc_MemoryScalable,
280:   0,
281:   0,
282:   0,
283:   0
284: };

288: PetscErrorCode  AOCreateMemoryScalable_private(MPI_Comm comm,PetscInt napp,const PetscInt from_array[],const PetscInt to_array[],AO ao, PetscInt *aomap_loc)
289: {
290:   PetscErrorCode    ierr;
291:   AO_MemoryScalable *aomems = (AO_MemoryScalable*)ao->data;
292:   PetscLayout       map     = aomems->map;
293:   PetscInt          n_local = map->n,i,j;
294:   PetscMPIInt       rank,size,tag;
295:   PetscInt          *owner,*start,*nprocs,nsends,nreceives;
296:   PetscInt          nmax,count,*sindices,*rindices,idx,lastidx;
297:   PetscInt          *owners = aomems->map->range;
298:   MPI_Request       *send_waits,*recv_waits;
299:   MPI_Status        recv_status;
300:   PetscMPIInt       nindices,widx;
301:   PetscInt          *rbuf;
302:   PetscInt          n=napp,ip,ia;
303:   MPI_Status        *send_status;

306:   PetscMemzero(aomap_loc,n_local*sizeof(PetscInt));

308:   MPI_Comm_rank(comm,&rank);
309:   MPI_Comm_size(comm,&size);

311:   /*  first count number of contributors (of from_array[]) to each processor */
312:   PetscMalloc(2*size*sizeof(PetscInt),&nprocs);
313:   PetscMemzero(nprocs,2*size*sizeof(PetscInt));
314:   PetscMalloc(n*sizeof(PetscInt),&owner);

316:   j       = 0;
317:   lastidx = -1;
318:   for (i=0; i<n; i++) {
319:     /* if indices are NOT locally sorted, need to start search at the beginning */
320:     if (lastidx > (idx = from_array[i])) j = 0;
321:     lastidx = idx;
322:     for (; j<size; j++) {
323:       if (idx >= owners[j] && idx < owners[j+1]) {
324:         nprocs[2*j]  += 2; /* num of indices to be sent - in pairs (ip,ia) */
325:         nprocs[2*j+1] = 1; /* send to proc[j] */
326:         owner[i]      = j;
327:         break;
328:       }
329:     }
330:   }
331:   nprocs[2*rank]=nprocs[2*rank+1]=0; /* do not receive from self! */
332:   nsends        = 0;
333:   for (i=0; i<size; i++) nsends += nprocs[2*i+1];

335:   /* inform other processors of number of messages and max length*/
336:   PetscMaxSum(comm,nprocs,&nmax,&nreceives);

338:   /* allocate arrays */
339:   PetscObjectGetNewTag((PetscObject)ao,&tag);
340:   PetscMalloc2(nreceives*nmax,PetscInt,&rindices,nreceives,MPI_Request,&recv_waits);
341:   PetscMalloc3(2*n,PetscInt,&sindices,nsends,MPI_Request,&send_waits,nsends,MPI_Status,&send_status);
342:   PetscMalloc(size*sizeof(PetscInt),&start);

344:   /* post receives: */
345:   for (i=0; i<nreceives; i++) {
346:     MPI_Irecv(rindices+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);
347:   }

349:   /* do sends:
350:       1) starts[i] gives the starting index in svalues for stuff going to
351:          the ith processor
352:   */
353:   start[0] = 0;
354:   for (i=1; i<size; i++) start[i] = start[i-1] + nprocs[2*i-2];
355:   for (i=0; i<n; i++) {
356:     j = owner[i];
357:     if (j != rank) {
358:       ip                   = from_array[i];
359:       ia                   = to_array[i];
360:       sindices[start[j]++] = ip;
361:       sindices[start[j]++] = ia;
362:     } else { /* compute my own map */
363:       ip            = from_array[i] - owners[rank];
364:       ia            = to_array[i];
365:       aomap_loc[ip] = ia;
366:     }
367:   }

369:   start[0] = 0;
370:   for (i=1; i<size; i++) start[i] = start[i-1] + nprocs[2*i-2];
371:   for (i=0,count=0; i<size; i++) {
372:     if (nprocs[2*i+1]) {
373:       MPI_Isend(sindices+start[i],nprocs[2*i],MPIU_INT,i,tag,comm,send_waits+count);
374:       count++;
375:     }
376:   }
377:   if (nsends != count) SETERRQ2(comm,PETSC_ERR_SUP,"nsends %d != count %d",nsends,count);

379:   /* wait on sends */
380:   if (nsends) {
381:     MPI_Waitall(nsends,send_waits,send_status);
382:   }

384:   /* recvs */
385:   count=0;
386:   for (j= nreceives; j>0; j--) {
387:     MPI_Waitany(nreceives,recv_waits,&widx,&recv_status);
388:     MPI_Get_count(&recv_status,MPIU_INT,&nindices);
389:     rbuf = rindices+nmax*widx; /* global index */

391:     /* compute local mapping */
392:     for (i=0; i<nindices; i+=2) { /* pack aomap_loc */
393:       ip            = rbuf[i] - owners[rank]; /* local index */
394:       ia            = rbuf[i+1];
395:       aomap_loc[ip] = ia;
396:     }
397:     count++;
398:   }

400:   PetscFree(start);
401:   PetscFree3(sindices,send_waits,send_status);
402:   PetscFree2(rindices,recv_waits);
403:   PetscFree(owner);
404:   PetscFree(nprocs);
405:   return(0);
406: }

410: PETSC_EXTERN PetscErrorCode AOCreate_MemoryScalable(AO ao)
411: {
412:   PetscErrorCode    ierr;
413:   IS                isapp=ao->isapp,ispetsc=ao->ispetsc;
414:   const PetscInt    *mypetsc,*myapp;
415:   PetscInt          napp,n_local,N,i,start,*petsc,*lens,*disp;
416:   MPI_Comm          comm;
417:   AO_MemoryScalable *aomems;
418:   PetscLayout       map;
419:   PetscMPIInt       size,rank;

422:   /* create special struct aomems */
423:   PetscNewLog(ao, AO_MemoryScalable, &aomems);
424:   ao->data = (void*) aomems;
425:   PetscMemcpy(ao->ops,&AOOps_MemoryScalable,sizeof(struct _AOOps));
426:   PetscObjectChangeTypeName((PetscObject)ao,AOMEMORYSCALABLE);

428:   /* transmit all local lengths of isapp to all processors */
429:   PetscObjectGetComm((PetscObject)isapp,&comm);
430:   MPI_Comm_size(comm, &size);
431:   MPI_Comm_rank(comm, &rank);
432:   PetscMalloc2(size,PetscInt,&lens,size,PetscInt,&disp);
433:   ISGetLocalSize(isapp,&napp);
434:   MPI_Allgather(&napp, 1, MPIU_INT, lens, 1, MPIU_INT, comm);

436:   N = 0;
437:   for (i = 0; i < size; i++) {
438:     disp[i] = N;
439:     N      += lens[i];
440:   }

442:   /* If ispetsc is 0 then use "natural" numbering */
443:   if (napp) {
444:     if (!ispetsc) {
445:       start = disp[rank];
446:       PetscMalloc((napp+1) * sizeof(PetscInt), &petsc);
447:       for (i=0; i<napp; i++) petsc[i] = start + i;
448:     } else {
449:       ISGetIndices(ispetsc,&mypetsc);
450:       petsc = (PetscInt*)mypetsc;
451:     }
452:   }

454:   /* create a map with global size N - used to determine the local sizes of ao - shall we use local napp instead of N? */
455:   PetscLayoutCreate(comm,&map);
456:   map->bs = 1;
457:   map->N  = N;
458:   PetscLayoutSetUp(map);

460:   ao->N       = N;
461:   ao->n       = map->n;
462:   aomems->map = map;

464:   /* create distributed indices app_loc: petsc->app and petsc_loc: app->petsc */
465:   n_local = map->n;
466:   PetscMalloc2(n_local,PetscInt, &aomems->app_loc,n_local,PetscInt,&aomems->petsc_loc);
467:   PetscLogObjectMemory(ao,2*n_local*sizeof(PetscInt));
468:   PetscMemzero(aomems->app_loc,n_local*sizeof(PetscInt));
469:   PetscMemzero(aomems->petsc_loc,n_local*sizeof(PetscInt));
470:   ISGetIndices(isapp,&myapp);

472:   AOCreateMemoryScalable_private(comm,napp,petsc,myapp,ao,aomems->app_loc);
473:   AOCreateMemoryScalable_private(comm,napp,myapp,petsc,ao,aomems->petsc_loc);

475:   ISRestoreIndices(isapp,&myapp);
476:   if (napp) {
477:     if (ispetsc) {
478:       ISRestoreIndices(ispetsc,&mypetsc);
479:     } else {
480:       PetscFree(petsc);
481:     }
482:   }
483:   PetscFree2(lens,disp);
484:   return(0);
485: }

489: /*@C
490:    AOCreateMemoryScalable - Creates a memory scalable application ordering using two integer arrays.

492:    Collective on MPI_Comm

494:    Input Parameters:
495: +  comm - MPI communicator that is to share AO
496: .  napp - size of integer arrays
497: .  myapp - integer array that defines an ordering
498: -  mypetsc - integer array that defines another ordering (may be NULL to
499:              indicate the natural ordering, that is 0,1,2,3,...)

501:    Output Parameter:
502: .  aoout - the new application ordering

504:    Level: beginner

506:     Notes: The arrays myapp and mypetsc must contain the all the integers 0 to napp-1 with no duplicates; that is there cannot be any "holes"
507:            in the indices. Use AOCreateMapping() or AOCreateMappingIS() if you wish to have "holes" in the indices.
508:            Comparing with AOCreateBasic(), this routine trades memory with message communication.

510: .keywords: AO, create

512: .seealso: AOCreateMemoryScalableIS(), AODestroy(), AOPetscToApplication(), AOApplicationToPetsc()
513: @*/
514: PetscErrorCode AOCreateMemoryScalable(MPI_Comm comm,PetscInt napp,const PetscInt myapp[],const PetscInt mypetsc[],AO *aoout)
515: {
517:   IS             isapp,ispetsc;
518:   const PetscInt *app=myapp,*petsc=mypetsc;

521:   ISCreateGeneral(comm,napp,app,PETSC_USE_POINTER,&isapp);
522:   if (mypetsc) {
523:     ISCreateGeneral(comm,napp,petsc,PETSC_USE_POINTER,&ispetsc);
524:   } else {
525:     ispetsc = NULL;
526:   }
527:   AOCreateMemoryScalableIS(isapp,ispetsc,aoout);
528:   ISDestroy(&isapp);
529:   if (mypetsc) {
530:     ISDestroy(&ispetsc);
531:   }
532:   return(0);
533: }

537: /*@C
538:    AOCreateMemoryScalableIS - Creates a memory scalable application ordering using two index sets.

540:    Collective on IS

542:    Input Parameters:
543: +  isapp - index set that defines an ordering
544: -  ispetsc - index set that defines another ordering (may be NULL to use the
545:              natural ordering)

547:    Output Parameter:
548: .  aoout - the new application ordering

550:    Level: beginner

552:     Notes: The index sets isapp and ispetsc must contain the all the integers 0 to napp-1 (where napp is the length of the index sets) with no duplicates;
553:            that is there cannot be any "holes".
554:            Comparing with AOCreateBasicIS(), this routine trades memory with message communication.
555: .keywords: AO, create

557: .seealso: AOCreateMemoryScalable(),  AODestroy()
558: @*/
559: PetscErrorCode  AOCreateMemoryScalableIS(IS isapp,IS ispetsc,AO *aoout)
560: {
562:   MPI_Comm       comm;
563:   AO             ao;

566:   PetscObjectGetComm((PetscObject)isapp,&comm);
567:   AOCreate(comm,&ao);
568:   AOSetIS(ao,isapp,ispetsc);
569:   AOSetType(ao,AOMEMORYSCALABLE);
570:   AOViewFromOptions(ao,NULL,"-ao_view");
571:   *aoout = ao;
572:   return(0);
573: }