static int serial_fm2 (ZZ *zz,
HGraph *hg,
int p,
float *part_sizes,
Partition part,
PHGPartParams *hgp,
float bal_tol)
{
int i, j, vertex, edge, *pins[2], *locked = 0, *locked_list = 0, round = 0;
double total_weight, part_weight[2], max_weight[2];
double cutsize_beforepass, best_cutsize, *gain = 0;
HEAP heap[2];
int steplimit;
char *yo="serial_fm2";
int part_dim = (hg->VtxWeightDim ? hg->VtxWeightDim : 1);
#ifdef HANDLE_ISOLATED_VERTICES
int isocnt=0;
#endif
#ifdef _DEBUG
double tw0, imbal, cutsize;
#endif
double error, best_error;
int best_imbalance, imbalance;
if (p != 2) {
ZOLTAN_PRINT_ERROR(zz->Proc, yo, "p!=2 not allowed for local_fm2.");
return ZOLTAN_FATAL;
}
if (hg->nEdge == 0)
return ZOLTAN_OK;
/* Calculate the weights in each partition and total, then maxima */
part_weight[0] = 0.0;
part_weight[1] = 0.0;
if (hg->vwgt) {
for (i = 0; i < hg->nVtx; i++)
part_weight[part[i]] += hg->vwgt[i*hg->VtxWeightDim];
total_weight = part_weight[0] + part_weight[1];
}
else {
total_weight = (double)(hg->nVtx);
for (i = 0; i < hg->nVtx; i++)
part_weight[part[i]] += 1.0;
}
max_weight[0] = total_weight * bal_tol * part_sizes[0];
max_weight[1] = total_weight * bal_tol * part_sizes[part_dim];
#ifdef _DEBUG
tw0 = total_weight * part_sizes[0];
#endif
if (!(pins[0] = (int*) ZOLTAN_CALLOC(2*hg->nEdge, sizeof(int)))
|| !(locked = (int*) ZOLTAN_CALLOC(hg->nVtx, sizeof(int)))
|| !(locked_list = (int*) ZOLTAN_CALLOC(hg->nVtx, sizeof(int)))
|| !(gain = (double*)ZOLTAN_CALLOC(hg->nVtx, sizeof(double))) ) {
Zoltan_Multifree(__FILE__,__LINE__, 4, &pins[0], &locked, &locked_list,
&gain);
ZOLTAN_PRINT_ERROR(zz->Proc, yo, "Insufficient memory.");
return ZOLTAN_MEMERR;
}
pins[1] = &(pins[0][hg->nEdge]);
/* Initial calculation of the pins distribution and gain values */
for (i = 0; i < hg->nEdge; i++)
for (j = hg->hindex[i]; j < hg->hindex[i+1]; j++)
(pins[part[hg->hvertex[j]]][i])++;
for (i = 0; i < hg->nVtx; i++)
for (j = hg->vindex[i]; j < hg->vindex[i+1]; j++) {
edge = hg->vedge[j];
if (pins[part[i]][edge] == 1)
gain[i] += (hg->ewgt ? hg->ewgt[edge] : 1.0);
else if (pins[1-part[i]][edge] == 0)
gain[i] -= (hg->ewgt ? hg->ewgt[edge] : 1.0);
}
/* Initialize the heaps and fill them with the gain values */
Zoltan_Heap_Init(zz, &heap[0], hg->nVtx);
Zoltan_Heap_Init(zz, &heap[1], hg->nVtx);
for (i = 0; i < hg->nVtx; i++)
if (!hgp->UseFixedVtx || hg->fixed_part[i]<0) {
#ifdef HANDLE_ISOLATED_VERTICES
if (hg->vindex[i+1]==hg->vindex[i]) { /* isolated vertex */
part_weight[part[i]] -= (hg->vwgt ? hg->vwgt[i*hg->VtxWeightDim]
: 1.0);
part[i] = -(part[i]+1); /* remove those vertices from that part*/
++isocnt;
} else
#endif
Zoltan_Heap_Input(&heap[part[i]], i, gain[i]);
}
#ifdef _DEBUG
else {
int pp = (hg->fixed_part[i] < hg->bisec_split) ? 0 : 1;
if (part[i]!=pp)
errexit("%s: beginning of pass for hg->info=%d vertex %d is fixed at %d bisec_split is %d but its part is %d\n", uMe(hg->comm), hg->info, i, hg->fixed_part[i], hg->bisec_split, part[i]);
}
#endif
Zoltan_Heap_Make(&heap[0]);
Zoltan_Heap_Make(&heap[1]);
/* Initialize given partition as best partition */
best_cutsize = cutsize_beforepass = Zoltan_PHG_Compute_NetCut(hg->comm, hg, part);
best_error = MAX (part_weight[0]-max_weight[0], part_weight[1]-max_weight[1]);
best_imbalance = (part_weight[0]>max_weight[0])||(part_weight[1]>max_weight[1]);
do {
int step = 0, no_better_steps = 0, number_locked = 0, best_locked = 0;
int sour, dest;
double cur_cutsize=best_cutsize;
round++;
cutsize_beforepass = best_cutsize;
if (hgp->output_level > PHG_DEBUG_LIST)
printf("ROUND %d:\nSTEP VERTEX PARTS MAX_WGT CHANGE CUTSIZE\n",round);
steplimit = (hgp->fm_max_neg_move < 0) ? hg->nVtx : hgp->fm_max_neg_move;
/* steplimit = hg->nVtx/4; Robsys previous choice */
while (step < hg->nVtx && no_better_steps < steplimit) {
step++;
no_better_steps++;
if (Zoltan_Heap_Empty(&heap[0]))
sour = 1;
else if (Zoltan_Heap_Empty(&heap[1]))
sour = 0;
else if (part_weight[0] > max_weight[0])
sour = 0;
else if (part_weight[1] > max_weight[1])
sour = 1;
else if (Zoltan_Heap_Max_Value(&heap[0])
> Zoltan_Heap_Max_Value(&heap[1]))
sour = 0;
else
sour = 1;
dest = 1-sour;
vertex = Zoltan_Heap_Extract_Max(&heap[sour]);
if (vertex<0)
break;
locked[vertex] = part[vertex] + 1;
locked_list[number_locked++] = vertex;
cur_cutsize -= gain[vertex];
Zoltan_HG_move_vertex (hg, vertex, sour, dest, part, pins, gain, heap);
#ifdef _DEBUG
imbal = (tw0==0.0) ? 0.0 : (part_weight[0]-tw0)/tw0;
uprintf(hg->comm, "%4d: SEQ moving %4d from %d to %d cut=%6.0lf bal=%.3lf\n", step, vertex, sour, dest, cur_cutsize, imbal);
/* Just for debugging */
cutsize = Zoltan_PHG_Compute_NetCut(hg->comm, hg, part);
if (cur_cutsize!=cutsize) {
errexit("%s: SEQ after move cutsize=%.2lf Verify: total=%.2lf\n", uMe(hg->comm), cur_cutsize,
cutsize);
}
#endif
part_weight[sour] -= (hg->vwgt ? hg->vwgt[vertex*hg->VtxWeightDim]
: 1.0);
part_weight[dest] += (hg->vwgt ? hg->vwgt[vertex*hg->VtxWeightDim]
: 1.0);
error = MAX (part_weight[0]-max_weight[0],part_weight[1]-max_weight[1]);
imbalance = (part_weight[0]>max_weight[0])||(part_weight[1]>max_weight[1]);
if ( ( best_imbalance && (error < best_error))
|| (!imbalance && (cur_cutsize < best_cutsize))) {
best_error = error;
best_imbalance = imbalance;
best_locked = number_locked;
best_cutsize = cur_cutsize;
no_better_steps = 0;
}
if (hgp->output_level > PHG_DEBUG_LIST+1)
printf ("%4d %6d %2d->%2d %7.2f %f %f\n", step, vertex, sour, dest,
error, cur_cutsize - cutsize_beforepass, cur_cutsize);
}
#ifdef _DEBUG
uprintf(hg->comm, "SEQ Best CUT=%6.0lf at move %d\n", best_cutsize, best_locked);
#endif
/* rollback */
while (number_locked != best_locked) {
vertex = locked_list[--number_locked];
sour = part[vertex];
dest = locked[vertex] - 1;
Zoltan_HG_move_vertex (hg, vertex, sour, dest, part, pins, gain, heap);
part_weight[sour] -= (hg->vwgt ? hg->vwgt[vertex*hg->VtxWeightDim]
: 1.0);
part_weight[dest] += (hg->vwgt ? hg->vwgt[vertex*hg->VtxWeightDim]
: 1.0);
Zoltan_Heap_Input(&heap[dest], vertex, gain[vertex]);
locked[vertex] = 0;
}
/* only update data structures if we're going to do another pass */
if ((best_cutsize < cutsize_beforepass) && (round < hgp->fm_loop_limit)) {
while (number_locked) {
vertex = locked_list[--number_locked];
locked[vertex] = 0;
Zoltan_Heap_Input(&heap[part[vertex]], vertex, gain[vertex]);
}
Zoltan_Heap_Make(&(heap[0]));
Zoltan_Heap_Make(&(heap[1]));
}
} while ((best_cutsize < cutsize_beforepass) && (round < hgp->fm_loop_limit));
#ifdef HANDLE_ISOLATED_VERTICES
if (isocnt) {
#ifdef _DEBUG
double isoimbalbefore, isoimbal;
#endif
double targetw0;
targetw0 = total_weight * part_sizes[0];
#ifdef _DEBUG
isoimbalbefore = (targetw0==0) ? 0.0 : (part_weight[0] - targetw0)/ targetw0;
#endif
for (i=0; i < hg->nVtx; ++i)
if (!hgp->UseFixedVtx || hg->fixed_part[i]<0) {
if (hg->vindex[i+1]==hg->vindex[i]) { /* go over isolated vertices */
int npno = (part_weight[0] < targetw0) ? 0 : 1;
part_weight[npno] += (hg->vwgt ? hg->vwgt[i*hg->VtxWeightDim]
: 1.0);
part[i] = npno;
}
}
#ifdef _DEBUG
isoimbal = (targetw0==0) ? 0.0 : (part_weight[0] - targetw0)/ targetw0;
uprintf(hg->comm, "SEQ %d isolated vertices, balance before: %.3lf after: %.3lf\n", isocnt, isoimbalbefore, isoimbal);
#endif
}
#endif
/* gain_check (hg, gain, part, pins); */
Zoltan_Multifree(__FILE__,__LINE__, 4, &pins[0], &locked, &locked_list, &gain);
Zoltan_Heap_Free(&heap[0]);
Zoltan_Heap_Free(&heap[1]);
return ZOLTAN_OK;
}
static int greedy_grow_part (
ZZ *zz,
HGraph *hg, /* Hypergraph. */
int start_vtx, /* Start the ordering from this vertex. */
int p, /* Number of partitions (must be 2). */
float *part_sizes, /* Array of length p containing the percentages of
work to be assigned to each partition. */
Partition part, /* Output: Partition array. */
PHGPartParams *hgp /* Partitioning parameters. */
)
{
int i, j, vtx, edge, edgesize;
int *cut[2];
double *gain = NULL;
int vwgtdim = hg->VtxWeightDim;
int part_dim = (hg->VtxWeightDim ? hg->VtxWeightDim : 1);
double weight_sum, part_sum;
double cutoff;
double psize_sum= 0.0;
HEAP h[2];
static char *yo = "greedy_grow_part";
int err=ZOLTAN_OK;
/* Allocate arrays. */
if (!(gain = (double*) ZOLTAN_CALLOC (hg->nVtx, sizeof (double)))){
ZOLTAN_PRINT_ERROR(zz->Proc, yo, "Insufficient memory.");
err = ZOLTAN_MEMERR;
goto End;
}
/* Initially put all vertices in part 0, except fixed ones. */
for (i=0; i<hg->nVtx; i++)
part[i] = 0;
if (hgp->UsePrefPart){
for (i=0; i<hg->nVtx; i++)
if ((hg->bisec_split >= 0) && (hg->pref_part[i] >= hg->bisec_split))
part[i] = 1;
}
cut[0] = (int*) ZOLTAN_CALLOC (2*hg->nEdge, sizeof (int));
if ((hg->nEdge > 0 && cut[0] == NULL) ) {
ZOLTAN_PRINT_ERROR(zz->Proc, yo, "Insufficient memory.");
err = ZOLTAN_MEMERR;
goto End;
}
cut[1] = &(cut[0][hg->nEdge]);
/* Initialize cut values. */
for (i=0; i<hg->nEdge; i++)
for (j=hg->hindex[i]; j<hg->hindex[i+1]; j++)
(cut[part[hg->hvertex[j]]][i])++;
/* Initialize gain values. */
for (i=0; i<hg->nVtx; i++){
/* compute gain only if vertex is free */
if (!hgp->UseFixedVtx || (hg->fixed_part[i] < 0))
for (j=hg->vindex[i]; j<hg->vindex[i+1]; j++) {
edge = hg->vedge[j];
edgesize = cut[0][edge]+cut[1][edge];
/* if edge is not cut by fixed vertices, update gain value */
if (MIN(cut[0][edge],cut[1][edge])==0)
gain[i] -= (hg->ewgt ? (hg->ewgt[edge]) : 1.0);
if (edgesize>1 && cut[part[i]][edge]==1)
gain[i] += (hg->ewgt ? (hg->ewgt[edge]) : 1.0);
}
}
/* Sum total weights. (No multi-weights yet) */
weight_sum = 0.;
part_sum = 0.0; /* Weight in the growing partition (1) */
for (i=0; i<hg->nVtx; i++){
weight_sum += hg->vwgt[i*vwgtdim];
if (part[i]>0)
part_sum += hg->vwgt[i*vwgtdim];
}
/* Set cutoff for growing partition (1) */
psize_sum = part_sizes[0] + part_sizes[part_dim];
cutoff = weight_sum*part_sizes[part_dim]/psize_sum;
if (hgp->output_level >= PHG_DEBUG_ALL)
printf("Debug: Starting new greedy growing at vertex %d, part=%2d\n", start_vtx, p);
/* Initialize heap. */
if (!hgp->UseFixedVtx)
gain[start_vtx] = 1e10; /* Make start_vtx max value in heap. */
/* All other values should be negative. */
Zoltan_Heap_Init(zz, &h[0], hg->nVtx);
Zoltan_Heap_Init(zz, &h[1], 0); /* Dummy heap, not used. */
for (i=0; i<hg->nVtx; i++){
/* Insert all non-fixed vertices into heap. */
if (!hgp->UseFixedVtx || (hg->fixed_part[i] < 0))
Zoltan_Heap_Input(h, i, gain[i]);
}
Zoltan_Heap_Make(h);
while (part_sum < cutoff) {
/* Get next vertex from heap */
vtx = Zoltan_Heap_Extract_Max(h);
if (vtx < 0) {
/* Empty heap: This can only happen if all vertices are fixed. */
break;
}
part_sum += hg->vwgt[vtx*vwgtdim];
part[vtx] = 1;
if (hgp->output_level >= PHG_DEBUG_PRINT)
printf("COARSE_PART vtx=%2d, part[%2d]=%2d, part_sum=%f\n",
vtx,vtx,part[vtx],part_sum);
/* Move vertex from part=0 to part=1. */
/* Update gain values for nbors. */
/* We use Zoltan_HG_move_vertex from the refinement code. */
Zoltan_HG_move_vertex(hg, vtx, 0, 1, part, cut, gain, h);
}
End:
ZOLTAN_FREE (&gain);
if (cut[0]) ZOLTAN_FREE (&cut[0]);
Zoltan_Heap_Free (&h[0]);
Zoltan_Heap_Free( &h[1]);
return err;
}
