/*************************************************************************
* This function is the entry point of the initial partition algorithm
* that does recursive bissection.
* This algorithm assembles the graph to all the processors and preceeds
* by parallelizing the recursive bisection step.
**************************************************************************/
void InitPartition(ctrl_t *ctrl, graph_t *graph)
{
idx_t i, j, ncon, mype, npes, gnvtxs, ngroups;
idx_t *xadj, *adjncy, *adjwgt, *vwgt;
idx_t *part, *gwhere0, *gwhere1;
idx_t *tmpwhere, *tmpvwgt, *tmpxadj, *tmpadjncy, *tmpadjwgt;
graph_t *agraph;
idx_t lnparts, fpart, fpe, lnpes;
idx_t twoparts=2, moptions[METIS_NOPTIONS], edgecut, max_cut;
real_t *tpwgts, *tpwgts2, *lbvec, lbsum, min_lbsum, wsum;
MPI_Comm ipcomm;
struct {
double sum;
int rank;
} lpesum, gpesum;
WCOREPUSH;
ncon = graph->ncon;
ngroups = gk_max(gk_min(RIP_SPLIT_FACTOR, ctrl->npes), 1);
IFSET(ctrl->dbglvl, DBG_TIME, gkMPI_Barrier(ctrl->comm));
IFSET(ctrl->dbglvl, DBG_TIME, starttimer(ctrl->InitPartTmr));
lbvec = rwspacemalloc(ctrl, ncon);
/* assemble the graph to all the processors */
agraph = AssembleAdaptiveGraph(ctrl, graph);
gnvtxs = agraph->nvtxs;
/* make a copy of the graph's structure for later */
xadj = icopy(gnvtxs+1, agraph->xadj, iwspacemalloc(ctrl, gnvtxs+1));
vwgt = icopy(gnvtxs*ncon, agraph->vwgt, iwspacemalloc(ctrl, gnvtxs*ncon));
adjncy = icopy(agraph->nedges, agraph->adjncy, iwspacemalloc(ctrl, agraph->nedges));
adjwgt = icopy(agraph->nedges, agraph->adjwgt, iwspacemalloc(ctrl, agraph->nedges));
part = iwspacemalloc(ctrl, gnvtxs);
/* create different processor groups */
gkMPI_Comm_split(ctrl->gcomm, ctrl->mype % ngroups, 0, &ipcomm);
gkMPI_Comm_rank(ipcomm, &mype);
gkMPI_Comm_size(ipcomm, &npes);
/* Go into the recursive bisection */
METIS_SetDefaultOptions(moptions);
moptions[METIS_OPTION_SEED] = ctrl->sync + (ctrl->mype % ngroups) + 1;
tpwgts = ctrl->tpwgts;
tpwgts2 = rwspacemalloc(ctrl, 2*ncon);
lnparts = ctrl->nparts;
fpart = fpe = 0;
lnpes = npes;
while (lnpes > 1 && lnparts > 1) {
/* determine the weights of the two partitions as a function of the
weight of the target partition weights */
for (j=(lnparts>>1), i=0; i<ncon; i++) {
tpwgts2[i] = rsum(j, tpwgts+fpart*ncon+i, ncon);
tpwgts2[ncon+i] = rsum(lnparts-j, tpwgts+(fpart+j)*ncon+i, ncon);
wsum = 1.0/(tpwgts2[i] + tpwgts2[ncon+i]);
tpwgts2[i] *= wsum;
tpwgts2[ncon+i] *= wsum;
}
METIS_PartGraphRecursive(&agraph->nvtxs, &ncon, agraph->xadj, agraph->adjncy,
agraph->vwgt, NULL, agraph->adjwgt, &twoparts, tpwgts2, NULL, moptions,
&edgecut, part);
/* pick one of the branches */
if (mype < fpe+lnpes/2) {
KeepPart(ctrl, agraph, part, 0);
lnpes = lnpes/2;
lnparts = lnparts/2;
}
else {
KeepPart(ctrl, agraph, part, 1);
fpart = fpart + lnparts/2;
fpe = fpe + lnpes/2;
lnpes = lnpes - lnpes/2;
lnparts = lnparts - lnparts/2;
}
}
gwhere0 = iset(gnvtxs, 0, iwspacemalloc(ctrl, gnvtxs));
gwhere1 = iwspacemalloc(ctrl, gnvtxs);
if (lnparts == 1) { /* Case npes is greater than or equal to nparts */
/* Only the first process will assign labels (for the reduction to work) */
if (mype == fpe) {
for (i=0; i<agraph->nvtxs; i++)
gwhere0[agraph->label[i]] = fpart;
}
}
else { /* Case in which npes is smaller than nparts */
/* create the normalized tpwgts for the lnparts from ctrl->tpwgts */
tpwgts = rwspacemalloc(ctrl, lnparts*ncon);
for (j=0; j<ncon; j++) {
for (wsum=0.0, i=0; i<lnparts; i++) {
tpwgts[i*ncon+j] = ctrl->tpwgts[(fpart+i)*ncon+j];
wsum += tpwgts[i*ncon+j];
}
for (wsum=1.0/wsum, i=0; i<lnparts; i++)
tpwgts[i*ncon+j] *= wsum;
}
METIS_PartGraphKway(&agraph->nvtxs, &ncon, agraph->xadj, agraph->adjncy,
agraph->vwgt, NULL, agraph->adjwgt, &lnparts, tpwgts, NULL, moptions,
&edgecut, part);
for (i=0; i<agraph->nvtxs; i++)
gwhere0[agraph->label[i]] = fpart + part[i];
}
gkMPI_Allreduce((void *)gwhere0, (void *)gwhere1, gnvtxs, IDX_T, MPI_SUM, ipcomm);
if (ngroups > 1) {
tmpxadj = agraph->xadj;
tmpadjncy = agraph->adjncy;
tmpadjwgt = agraph->adjwgt;
tmpvwgt = agraph->vwgt;
tmpwhere = agraph->where;
agraph->xadj = xadj;
agraph->adjncy = adjncy;
agraph->adjwgt = adjwgt;
agraph->vwgt = vwgt;
agraph->where = gwhere1;
agraph->vwgt = vwgt;
agraph->nvtxs = gnvtxs;
edgecut = ComputeSerialEdgeCut(agraph);
ComputeSerialBalance(ctrl, agraph, gwhere1, lbvec);
lbsum = rsum(ncon, lbvec, 1);
gkMPI_Allreduce((void *)&edgecut, (void *)&max_cut, 1, IDX_T, MPI_MAX, ctrl->gcomm);
gkMPI_Allreduce((void *)&lbsum, (void *)&min_lbsum, 1, REAL_T, MPI_MIN, ctrl->gcomm);
lpesum.sum = lbsum;
if (min_lbsum < UNBALANCE_FRACTION*ncon) {
if (lbsum < UNBALANCE_FRACTION*ncon)
lpesum.sum = edgecut;
else
lpesum.sum = max_cut;
}
lpesum.rank = ctrl->mype;
gkMPI_Allreduce((void *)&lpesum, (void *)&gpesum, 1, MPI_DOUBLE_INT,
MPI_MINLOC, ctrl->gcomm);
gkMPI_Bcast((void *)gwhere1, gnvtxs, IDX_T, gpesum.rank, ctrl->gcomm);
agraph->xadj = tmpxadj;
agraph->adjncy = tmpadjncy;
agraph->adjwgt = tmpadjwgt;
agraph->vwgt = tmpvwgt;
agraph->where = tmpwhere;
}
icopy(graph->nvtxs, gwhere1+graph->vtxdist[ctrl->mype], graph->where);
FreeGraph(agraph);
gkMPI_Comm_free(&ipcomm);
IFSET(ctrl->dbglvl, DBG_TIME, gkMPI_Barrier(ctrl->comm));
IFSET(ctrl->dbglvl, DBG_TIME, stoptimer(ctrl->InitPartTmr));
WCOREPOP;
}
int CheckParams(ctrl_t *ctrl)
{
idx_t i, j;
real_t sum;
mdbglvl_et dbglvl=METIS_DBG_INFO;
switch (ctrl->optype) {
case METIS_OP_PMETIS:
if (ctrl->objtype != METIS_OBJTYPE_CUT) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect objective type.\n"));
return 0;
}
if (ctrl->ctype != METIS_CTYPE_RM && ctrl->ctype != METIS_CTYPE_SHEM) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect coarsening scheme.\n"));
return 0;
}
if (ctrl->iptype != METIS_IPTYPE_GROW && ctrl->iptype != METIS_IPTYPE_RANDOM) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect initial partitioning scheme.\n"));
return 0;
}
if (ctrl->rtype != METIS_RTYPE_FM) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect refinement scheme.\n"));
return 0;
}
if (ctrl->ncuts <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ncuts.\n"));
return 0;
}
if (ctrl->niter <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect niter.\n"));
return 0;
}
if (ctrl->ufactor <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ufactor.\n"));
return 0;
}
if (ctrl->numflag != 0 && ctrl->numflag != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect numflag.\n"));
return 0;
}
if (ctrl->nparts <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect nparts.\n"));
return 0;
}
if (ctrl->ncon <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ncon.\n"));
return 0;
}
for (i=0; i<ctrl->ncon; i++) {
sum = rsum(ctrl->nparts, ctrl->tpwgts+i, ctrl->ncon);
if (sum < 0.99 || sum > 1.01) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect sum of %"PRREAL" for tpwgts for constraint %"PRIDX".\n", sum, i));
return 0;
}
}
for (i=0; i<ctrl->ncon; i++) {
for (j=0; j<ctrl->nparts; j++) {
if (ctrl->tpwgts[j*ctrl->ncon+i] <= 0.0) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect tpwgts for partition %"PRIDX" and constraint %"PRIDX".\n", j, i));
return 0;
}
}
}
for (i=0; i<ctrl->ncon; i++) {
if (ctrl->ubfactors[i] <= 1.0) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect ubfactor for constraint %"PRIDX".\n", i));
return 0;
}
}
break;
case METIS_OP_KMETIS:
if (ctrl->objtype != METIS_OBJTYPE_CUT && ctrl->objtype != METIS_OBJTYPE_VOL) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect objective type.\n"));
return 0;
}
if (ctrl->ctype != METIS_CTYPE_RM && ctrl->ctype != METIS_CTYPE_SHEM) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect coarsening scheme.\n"));
return 0;
}
if (ctrl->iptype != METIS_IPTYPE_METISRB) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect initial partitioning scheme.\n"));
return 0;
}
if (ctrl->rtype != METIS_RTYPE_GREEDY) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect refinement scheme.\n"));
return 0;
}
if (ctrl->ncuts <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ncuts.\n"));
return 0;
}
if (ctrl->niter <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect niter.\n"));
return 0;
}
if (ctrl->ufactor <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ufactor.\n"));
return 0;
}
if (ctrl->numflag != 0 && ctrl->numflag != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect numflag.\n"));
return 0;
}
if (ctrl->nparts <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect nparts.\n"));
return 0;
}
if (ctrl->ncon <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ncon.\n"));
return 0;
}
if (ctrl->contig != 0 && ctrl->contig != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect contig.\n"));
return 0;
}
if (ctrl->minconn != 0 && ctrl->minconn != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect minconn.\n"));
return 0;
}
for (i=0; i<ctrl->ncon; i++) {
sum = rsum(ctrl->nparts, ctrl->tpwgts+i, ctrl->ncon);
if (sum < 0.99 || sum > 1.01) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect sum of %"PRREAL" for tpwgts for constraint %"PRIDX".\n", sum, i));
return 0;
}
}
for (i=0; i<ctrl->ncon; i++) {
for (j=0; j<ctrl->nparts; j++) {
if (ctrl->tpwgts[j*ctrl->ncon+i] <= 0.0) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect tpwgts for partition %"PRIDX" and constraint %"PRIDX".\n", j, i));
return 0;
}
}
}
for (i=0; i<ctrl->ncon; i++) {
if (ctrl->ubfactors[i] <= 1.0) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect ubfactor for constraint %"PRIDX".\n", i));
return 0;
}
}
break;
case METIS_OP_OMETIS:
if (ctrl->objtype != METIS_OBJTYPE_NODE) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect objective type.\n"));
return 0;
}
if (ctrl->ctype != METIS_CTYPE_RM && ctrl->ctype != METIS_CTYPE_SHEM) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect coarsening scheme.\n"));
return 0;
}
if (ctrl->iptype != METIS_IPTYPE_EDGE && ctrl->iptype != METIS_IPTYPE_NODE) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect initial partitioning scheme.\n"));
return 0;
}
if (ctrl->rtype != METIS_RTYPE_SEP1SIDED && ctrl->rtype != METIS_RTYPE_SEP2SIDED) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect refinement scheme.\n"));
return 0;
}
if (ctrl->nseps <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect nseps.\n"));
return 0;
}
if (ctrl->niter <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect niter.\n"));
return 0;
}
if (ctrl->ufactor <= 0) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ufactor.\n"));
return 0;
}
if (ctrl->numflag != 0 && ctrl->numflag != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect numflag.\n"));
return 0;
}
if (ctrl->nparts != 3) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect nparts.\n"));
return 0;
}
if (ctrl->ncon != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ncon.\n"));
return 0;
}
if (ctrl->compress != 0 && ctrl->compress != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect compress.\n"));
return 0;
}
if (ctrl->ccorder != 0 && ctrl->ccorder != 1) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect ccorder.\n"));
return 0;
}
if (ctrl->pfactor < 0.0 ) {
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect pfactor.\n"));
return 0;
}
for (i=0; i<ctrl->ncon; i++) {
if (ctrl->ubfactors[i] <= 1.0) {
IFSET(dbglvl, METIS_DBG_INFO,
printf("Input Error: Incorrect ubfactor for constraint %"PRIDX".\n", i));
return 0;
}
}
break;
default:
IFSET(dbglvl, METIS_DBG_INFO, printf("Input Error: Incorrect optype\n"));
return 0;
}
return 1;
}
/*************************************************************************
* This function performs a k-way directed diffusion
**************************************************************************/
real_t WavefrontDiffusion(ctrl_t *ctrl, graph_t *graph, idx_t *home)
{
idx_t ii, i, j, k, l, nvtxs, nedges, nparts;
idx_t from, to, edge, done, nswaps, noswaps, totalv, wsize;
idx_t npasses, first, second, third, mind, maxd;
idx_t *xadj, *adjncy, *adjwgt, *where, *perm;
idx_t *rowptr, *colind, *ed, *psize;
real_t *transfer, *tmpvec;
real_t balance = -1.0, *load, *solution, *workspace;
real_t *nvwgt, *npwgts, flowFactor, cost, ubfactor;
matrix_t matrix;
ikv_t *cand;
idx_t ndirty, nclean, dptr, clean;
nvtxs = graph->nvtxs;
nedges = graph->nedges;
xadj = graph->xadj;
nvwgt = graph->nvwgt;
adjncy = graph->adjncy;
adjwgt = graph->adjwgt;
where = graph->where;
nparts = ctrl->nparts;
ubfactor = ctrl->ubvec[0];
matrix.nrows = nparts;
flowFactor = 0.35;
flowFactor = (ctrl->mype == 2) ? 0.50 : flowFactor;
flowFactor = (ctrl->mype == 3) ? 0.75 : flowFactor;
flowFactor = (ctrl->mype == 4) ? 1.00 : flowFactor;
/* allocate memory */
solution = rmalloc(4*nparts+2*nedges, "WavefrontDiffusion: solution");
tmpvec = solution + nparts;
npwgts = solution + 2*nparts;
load = solution + 3*nparts;
matrix.values = solution + 4*nparts;
transfer = matrix.transfer = solution + 4*nparts + nedges;
perm = imalloc(2*nvtxs+2*nparts+nedges+1, "WavefrontDiffusion: perm");
ed = perm + nvtxs;
psize = perm + 2*nvtxs;
rowptr = matrix.rowptr = perm + 2*nvtxs + nparts;
colind = matrix.colind = perm + 2*nvtxs + 2*nparts + 1;
/*GKTODO - Potential problem with this malloc */
wsize = gk_max(sizeof(real_t)*nparts*6, sizeof(idx_t)*(nvtxs+nparts*2+1));
workspace = (real_t *)gk_malloc(wsize, "WavefrontDiffusion: workspace");
cand = ikvmalloc(nvtxs, "WavefrontDiffusion: cand");
/*****************************/
/* Populate empty subdomains */
/*****************************/
iset(nparts, 0, psize);
for (i=0; i<nvtxs; i++)
psize[where[i]]++;
mind = iargmin(nparts, psize);
maxd = iargmax(nparts, psize);
if (psize[mind] == 0) {
for (i=0; i<nvtxs; i++) {
k = (RandomInRange(nvtxs)+i)%nvtxs;
if (where[k] == maxd) {
where[k] = mind;
psize[mind]++;
psize[maxd]--;
break;
}
}
}
iset(nvtxs, 0, ed);
rset(nparts, 0.0, npwgts);
for (i=0; i<nvtxs; i++) {
npwgts[where[i]] += nvwgt[i];
for (j=xadj[i]; j<xadj[i+1]; j++)
ed[i] += (where[i] != where[adjncy[j]] ? adjwgt[j] : 0);
}
ComputeLoad(graph, nparts, load, ctrl->tpwgts, 0);
done = 0;
/* zero out the tmpvec array */
rset(nparts, 0.0, tmpvec);
npasses = gk_min(nparts/2, NGD_PASSES);
for (l=0; l<npasses; l++) {
/* Set-up and solve the diffusion equation */
nswaps = 0;
/************************/
/* Solve flow equations */
/************************/
SetUpConnectGraph(graph, &matrix, (idx_t *)workspace);
/* check for disconnected subdomains */
for(i=0; i<matrix.nrows; i++) {
if (matrix.rowptr[i]+1 == matrix.rowptr[i+1]) {
cost = (real_t)(ctrl->mype);
goto CleanUpAndExit;
}
}
ConjGrad2(&matrix, load, solution, 0.001, workspace);
ComputeTransferVector(1, &matrix, solution, transfer, 0);
GetThreeMax(nparts, load, &first, &second, &third);
if (l%3 == 0) {
FastRandomPermute(nvtxs, perm, 1);
}
else {
/*****************************/
/* move dirty vertices first */
/*****************************/
ndirty = 0;
for (i=0; i<nvtxs; i++) {
if (where[i] != home[i])
ndirty++;
}
dptr = 0;
for (i=0; i<nvtxs; i++) {
if (where[i] != home[i])
perm[dptr++] = i;
else
perm[ndirty++] = i;
}
PASSERT(ctrl, ndirty == nvtxs);
ndirty = dptr;
nclean = nvtxs-dptr;
FastRandomPermute(ndirty, perm, 0);
FastRandomPermute(nclean, perm+ndirty, 0);
}
if (ctrl->mype == 0) {
for (j=nvtxs, k=0, ii=0; ii<nvtxs; ii++) {
i = perm[ii];
if (ed[i] != 0) {
cand[k].key = -ed[i];
cand[k++].val = i;
}
else {
cand[--j].key = 0;
cand[j].val = i;
}
}
ikvsorti(k, cand);
}
for (ii=0; ii<nvtxs/3; ii++) {
i = (ctrl->mype == 0) ? cand[ii].val : perm[ii];
from = where[i];
/* don't move out the last vertex in a subdomain */
if (psize[from] == 1)
continue;
clean = (from == home[i]) ? 1 : 0;
/* only move from top three or dirty vertices */
if (from != first && from != second && from != third && clean)
continue;
/* Scatter the sparse transfer row into the dense tmpvec row */
for (j=rowptr[from]+1; j<rowptr[from+1]; j++)
tmpvec[colind[j]] = transfer[j];
for (j=xadj[i]; j<xadj[i+1]; j++) {
to = where[adjncy[j]];
if (from != to) {
if (tmpvec[to] > (flowFactor * nvwgt[i])) {
tmpvec[to] -= nvwgt[i];
INC_DEC(psize[to], psize[from], 1);
INC_DEC(npwgts[to], npwgts[from], nvwgt[i]);
INC_DEC(load[to], load[from], nvwgt[i]);
where[i] = to;
nswaps++;
/* Update external degrees */
ed[i] = 0;
for (k=xadj[i]; k<xadj[i+1]; k++) {
edge = adjncy[k];
ed[i] += (to != where[edge] ? adjwgt[k] : 0);
if (where[edge] == from)
ed[edge] += adjwgt[k];
if (where[edge] == to)
ed[edge] -= adjwgt[k];
}
break;
}
}
}
/* Gather the dense tmpvec row into the sparse transfer row */
for (j=rowptr[from]+1; j<rowptr[from+1]; j++) {
transfer[j] = tmpvec[colind[j]];
tmpvec[colind[j]] = 0.0;
}
ASSERT(fabs(rsum(nparts, tmpvec, 1)) < .0001)
}
if (l % 2 == 1) {
balance = rmax(nparts, npwgts)*nparts;
if (balance < ubfactor + 0.035)
done = 1;
if (GlobalSESum(ctrl, done) > 0)
break;
noswaps = (nswaps > 0) ? 0 : 1;
if (GlobalSESum(ctrl, noswaps) > ctrl->npes/2)
break;
}
}
graph->mincut = ComputeSerialEdgeCut(graph);
totalv = Mc_ComputeSerialTotalV(graph, home);
cost = ctrl->ipc_factor * (real_t)graph->mincut + ctrl->redist_factor * (real_t)totalv;
CleanUpAndExit:
gk_free((void **)&solution, (void **)&perm, (void **)&workspace, (void **)&cand, LTERM);
return cost;
}
/*************************************************************************
* This function is the entry point of the initial balancing algorithm.
* This algorithm assembles the graph to all the processors and preceeds
* with the balancing step.
**************************************************************************/
void Balance_Partition(ctrl_t *ctrl, graph_t *graph)
{
idx_t i, j, nvtxs, nedges, ncon;
idx_t mype, npes, srnpes, srmype;
idx_t *vtxdist, *xadj, *adjncy, *adjwgt, *vwgt, *vsize;
idx_t *part, *lwhere, *home;
idx_t lnparts, fpart, fpe, lnpes, ngroups;
idx_t *rcounts, *rdispls;
idx_t twoparts=2, moptions[METIS_NOPTIONS], edgecut, max_cut;
idx_t sr_pe, gd_pe, sr, gd, who_wins;
real_t my_cut, my_totalv, my_cost = -1.0, my_balance = -1.0, wsum;
real_t rating, max_rating, your_cost = -1.0, your_balance = -1.0;
real_t lbsum, min_lbsum, *lbvec, *tpwgts, *tpwgts2, buffer[2];
graph_t *agraph, cgraph;
ctrl_t *myctrl;
MPI_Status status;
MPI_Comm ipcomm, srcomm;
struct {
double cost;
int rank;
} lpecost, gpecost;
IFSET(ctrl->dbglvl, DBG_TIME, starttimer(ctrl->InitPartTmr));
WCOREPUSH;
vtxdist = graph->vtxdist;
agraph = AssembleAdaptiveGraph(ctrl, graph);
nvtxs = cgraph.nvtxs = agraph->nvtxs;
nedges = cgraph.nedges = agraph->nedges;
ncon = cgraph.ncon = agraph->ncon;
xadj = cgraph.xadj = icopy(nvtxs+1, agraph->xadj, iwspacemalloc(ctrl, nvtxs+1));
vwgt = cgraph.vwgt = icopy(nvtxs*ncon, agraph->vwgt, iwspacemalloc(ctrl, nvtxs*ncon));
vsize = cgraph.vsize = icopy(nvtxs, agraph->vsize, iwspacemalloc(ctrl, nvtxs));
adjncy = cgraph.adjncy = icopy(nedges, agraph->adjncy, iwspacemalloc(ctrl, nedges));
adjwgt = cgraph.adjwgt = icopy(nedges, agraph->adjwgt, iwspacemalloc(ctrl, nedges));
part = cgraph.where = agraph->where = iwspacemalloc(ctrl, nvtxs);
lwhere = iwspacemalloc(ctrl, nvtxs);
home = iwspacemalloc(ctrl, nvtxs);
lbvec = rwspacemalloc(ctrl, graph->ncon);
/****************************************/
/****************************************/
if (ctrl->ps_relation == PARMETIS_PSR_UNCOUPLED) {
WCOREPUSH;
rcounts = iwspacemalloc(ctrl, ctrl->npes);
rdispls = iwspacemalloc(ctrl, ctrl->npes+1);
for (i=0; i<ctrl->npes; i++)
rdispls[i] = rcounts[i] = vtxdist[i+1]-vtxdist[i];
MAKECSR(i, ctrl->npes, rdispls);
gkMPI_Allgatherv((void *)graph->home, graph->nvtxs, IDX_T,
(void *)part, rcounts, rdispls, IDX_T, ctrl->comm);
for (i=0; i<agraph->nvtxs; i++)
home[i] = part[i];
WCOREPOP; /* local frees */
}
else {
for (i=0; i<ctrl->npes; i++) {
for (j=vtxdist[i]; j<vtxdist[i+1]; j++)
part[j] = home[j] = i;
}
}
/* Ensure that the initial partitioning is legal */
for (i=0; i<agraph->nvtxs; i++) {
if (part[i] >= ctrl->nparts)
part[i] = home[i] = part[i] % ctrl->nparts;
if (part[i] < 0)
part[i] = home[i] = (-1*part[i]) % ctrl->nparts;
}
/****************************************/
/****************************************/
IFSET(ctrl->dbglvl, DBG_REFINEINFO,
ComputeSerialBalance(ctrl, agraph, agraph->where, lbvec));
IFSET(ctrl->dbglvl, DBG_REFINEINFO,
rprintf(ctrl, "input cut: %"PRIDX", balance: ", ComputeSerialEdgeCut(agraph)));
for (i=0; i<agraph->ncon; i++)
IFSET(ctrl->dbglvl, DBG_REFINEINFO, rprintf(ctrl, "%.3"PRREAL" ", lbvec[i]));
IFSET(ctrl->dbglvl, DBG_REFINEINFO, rprintf(ctrl, "\n"));
/****************************************/
/* Split the processors into two groups */
/****************************************/
sr = (ctrl->mype % 2 == 0) ? 1 : 0;
gd = (ctrl->mype % 2 == 1) ? 1 : 0;
if (graph->ncon > MAX_NCON_FOR_DIFFUSION || ctrl->npes == 1) {
sr = 1;
gd = 0;
}
sr_pe = 0;
gd_pe = 1;
gkMPI_Comm_split(ctrl->gcomm, sr, 0, &ipcomm);
gkMPI_Comm_rank(ipcomm, &mype);
gkMPI_Comm_size(ipcomm, &npes);
if (sr == 1) { /* Half of the processors do scratch-remap */
ngroups = gk_max(gk_min(RIP_SPLIT_FACTOR, npes), 1);
gkMPI_Comm_split(ipcomm, mype % ngroups, 0, &srcomm);
gkMPI_Comm_rank(srcomm, &srmype);
gkMPI_Comm_size(srcomm, &srnpes);
METIS_SetDefaultOptions(moptions);
moptions[METIS_OPTION_SEED] = ctrl->sync + (mype % ngroups) + 1;
tpwgts = ctrl->tpwgts;
tpwgts2 = rwspacemalloc(ctrl, 2*ncon);
iset(nvtxs, 0, lwhere);
lnparts = ctrl->nparts;
fpart = fpe = 0;
lnpes = srnpes;
while (lnpes > 1 && lnparts > 1) {
PASSERT(ctrl, agraph->nvtxs > 1);
/* determine the weights of the two partitions as a function of the
weight of the target partition weights */
for (j=(lnparts>>1), i=0; i<ncon; i++) {
tpwgts2[i] = rsum(j, tpwgts+fpart*ncon+i, ncon);
tpwgts2[ncon+i] = rsum(lnparts-j, tpwgts+(fpart+j)*ncon+i, ncon);
wsum = 1.0/(tpwgts2[i] + tpwgts2[ncon+i]);
tpwgts2[i] *= wsum;
tpwgts2[ncon+i] *= wsum;
}
METIS_PartGraphRecursive(&agraph->nvtxs, &ncon, agraph->xadj,
agraph->adjncy, agraph->vwgt, NULL, agraph->adjwgt,
&twoparts, tpwgts2, NULL, moptions, &edgecut, part);
/* pick one of the branches */
if (srmype < fpe+lnpes/2) {
KeepPart(ctrl, agraph, part, 0);
lnpes = lnpes/2;
lnparts = lnparts/2;
}
else {
KeepPart(ctrl, agraph, part, 1);
fpart = fpart + lnparts/2;
fpe = fpe + lnpes/2;
lnpes = lnpes - lnpes/2;
lnparts = lnparts - lnparts/2;
}
}
if (lnparts == 1) { /* Case in which srnpes is greater or equal to nparts */
/* Only the first process will assign labels (for the reduction to work) */
if (srmype == fpe) {
for (i=0; i<agraph->nvtxs; i++)
lwhere[agraph->label[i]] = fpart;
}
}
else { /* Case in which srnpes is smaller than nparts */
/* create the normalized tpwgts for the lnparts from ctrl->tpwgts */
tpwgts = rwspacemalloc(ctrl, lnparts*ncon);
for (j=0; j<ncon; j++) {
for (wsum=0.0, i=0; i<lnparts; i++) {
tpwgts[i*ncon+j] = ctrl->tpwgts[(fpart+i)*ncon+j];
wsum += tpwgts[i*ncon+j];
}
for (wsum=1.0/wsum, i=0; i<lnparts; i++)
tpwgts[i*ncon+j] *= wsum;
}
METIS_PartGraphKway(&agraph->nvtxs, &ncon, agraph->xadj, agraph->adjncy,
agraph->vwgt, NULL, agraph->adjwgt, &lnparts, tpwgts, NULL, moptions,
&edgecut, part);
for (i=0; i<agraph->nvtxs; i++)
lwhere[agraph->label[i]] = fpart + part[i];
}
gkMPI_Allreduce((void *)lwhere, (void *)part, nvtxs, IDX_T, MPI_SUM, srcomm);
edgecut = ComputeSerialEdgeCut(&cgraph);
ComputeSerialBalance(ctrl, &cgraph, part, lbvec);
lbsum = rsum(ncon, lbvec, 1);
gkMPI_Allreduce((void *)&edgecut, (void *)&max_cut, 1, IDX_T, MPI_MAX, ipcomm);
gkMPI_Allreduce((void *)&lbsum, (void *)&min_lbsum, 1, REAL_T, MPI_MIN, ipcomm);
lpecost.rank = ctrl->mype;
lpecost.cost = lbsum;
if (min_lbsum < UNBALANCE_FRACTION * (real_t)(ncon)) {
if (lbsum < UNBALANCE_FRACTION * (real_t)(ncon))
lpecost.cost = (double)edgecut;
else
lpecost.cost = (double)max_cut + lbsum;
}
gkMPI_Allreduce((void *)&lpecost, (void *)&gpecost, 1, MPI_DOUBLE_INT,
MPI_MINLOC, ipcomm);
if (ctrl->mype == gpecost.rank && ctrl->mype != sr_pe)
gkMPI_Send((void *)part, nvtxs, IDX_T, sr_pe, 1, ctrl->comm);
if (ctrl->mype != gpecost.rank && ctrl->mype == sr_pe)
gkMPI_Recv((void *)part, nvtxs, IDX_T, gpecost.rank, 1, ctrl->comm, &status);
if (ctrl->mype == sr_pe) {
icopy(nvtxs, part, lwhere);
SerialRemap(ctrl, &cgraph, ctrl->nparts, home, lwhere, part, ctrl->tpwgts);
}
gkMPI_Comm_free(&srcomm);
}
