Пример #1
0
  int gpartition(const vector< set<int> > &graph, int npartitions, int partition_method, vector<int> &decomp){  
    // If no partitioning method is set, choose a default.
    if(partition_method<0){
      if(npartitions<=8)
        partition_method = 0; // METIS PartGraphRecursive
      else
        partition_method = 1; // METIS PartGraphKway
    }

    int nnodes = graph.size();

    // Compress graph    
    vector<idxtype> xadj(nnodes+1), adjncy;
    int pos=0;
    xadj[0]=1;
    for(int i=0;i<nnodes;i++){
      for(set<int>::iterator jt=graph[i].begin();jt!=graph[i].end();jt++){
        adjncy.push_back(*jt);
        pos++;
      }
      xadj[i+1] = pos+1;
    }
    
    // Partition graph
    decomp.resize(nnodes);
    int wgtflag=0, numflag=1, edgecut=0;
#ifdef PARMETIS_V3
    int options[] = {0};
#else
    idx_t nbc=1;
    idx_t options[METIS_NOPTIONS];
    METIS_SetDefaultOptions(options);
    options[METIS_OPTION_NUMBERING]=1;
#endif
    if(partition_method){
#ifdef PARMETIS_V3
      METIS_PartGraphKway(&nnodes, &(xadj[0]), &(adjncy[0]), NULL, NULL, &wgtflag, 
                          &numflag, &npartitions, options, &edgecut, &(decomp[0]));
#else
      METIS_PartGraphKway(&nnodes,&nbc,&(xadj[0]),&(adjncy[0]), NULL, NULL,NULL,
			  &npartitions, NULL, NULL,options,&edgecut,
			  &(decomp[0]));
#endif
    }else{
#ifdef PARMETIS_V3
      METIS_PartGraphRecursive(&nnodes, &(xadj[0]), &(adjncy[0]), NULL, NULL, &wgtflag, 
                               &numflag, &npartitions, options, &edgecut, &(decomp[0]));
#else
      METIS_PartGraphRecursive(&nnodes,&nbc,&(xadj[0]),&(adjncy[0]), NULL, NULL,NULL,
			  &npartitions, NULL, NULL,options,&edgecut,
			  &(decomp[0]));
#endif
    }
    
    // number from zero
    for(int i=0;i<nnodes;i++)
      decomp[i]--;

    return edgecut;
  }
Пример #2
0
void metis_wrapper(int *n, int *xadj, int *adjncy, int *nparts, int *part)
{
#ifndef METIS_VER_MAJOR
/* Metis 4.X (or METISLib in ParaMetis 3.X) */

  int edgecut;
  int wgtflag = 0;
  int numflag = 1;  /* fortran-stype numbering */
  int options[5] = { 0, 3, 1, 1, 0 };  /* default values */

  METIS_PartGraphRecursive(n, xadj, adjncy, NULL, NULL, &wgtflag, &numflag,
                           nparts, options, &edgecut, part);

#elif METIS_VER_MAJOR == 5
/* Metis 5.X */

  int edgecut;
  int ncon = 1;
  int options[METIS_NOPTIONS];

  METIS_SetDefaultOptions(options);
  options[METIS_OPTION_NUMBERING] = 1;  /* fortran-stype numbering */

  METIS_PartGraphRecursive(n, &ncon, xadj, adjncy, NULL, NULL, NULL,
                           nparts, NULL, NULL, options, &edgecut, part);

#else
#error unknown Metis version
#endif
}
Пример #3
0
/*Partition this mesh's elements into n chunks,
 writing each element's 0-based chunk number to elem2chunk.
*/
void FEM_Mesh_partition(const FEM_Mesh *mesh,int nchunks,int *elem2chunk, bool faceGraph)
{
	CkThresholdTimer time("FEM Split> Building graph for metis partitioner",1.0);
	int nelems=mesh->nElems();
	if (nchunks==1) { //Metis doesn't handle this case (!)
		for (int i=0;i<nelems;i++) elem2chunk[i]=0;
		return;
	}
	Graph g(nelems);
        if (!faceGraph) {
	    mesh2graph(mesh,&g);
        } else {
            mesh2graph_face(mesh,&g);
        }
	
	int *adjStart; /*Maps elem # -> start index in adjacency list*/
	int *adjList; /*Lists adjacent vertices for each element*/
	g.toAdjList(adjStart,adjList);

	int ecut,ncon=1;
	time.start("FEM Split> Calling metis partitioner");
	if (nchunks<8) /*Metis manual says recursive version is higher-quality here*/
	  METIS_PartGraphRecursive(&nelems, &ncon, adjStart, adjList, NULL, NULL, NULL,
                        &nchunks, NULL, NULL, NULL, &ecut, elem2chunk);
	else /*For many chunks, Kway is supposedly faster */
	  METIS_PartGraphKway(&nelems, &ncon, adjStart, adjList, NULL, NULL, NULL,
                        &nchunks, NULL, NULL, NULL, &ecut, elem2chunk);
	delete[] adjStart;
	delete[] adjList;
}
Пример #4
0
void FC_FUNC_(oct_metis_partgraphrecursive, OCT_METIS_PARTGRAPHRECURSIVE)
     (idx_t *nvtxs, idx_t *ncon, idx_t *xadj, idx_t *adjncy, idx_t *nparts, 
      real_t *tpwgts, real_t *ubvec, idx_t *options, idx_t *objval, idx_t *part)
{

  METIS_PartGraphRecursive(nvtxs, ncon, xadj, adjncy, NULL, NULL, NULL, nparts, 
			   tpwgts, ubvec, options, objval, part);
}
Пример #5
0
	void decompose(Graph_part & gp)
	{
		// Decompose
		METIS_PartGraphRecursive(Mg.nvtxs, Mg.ncon, Mg.xadj, Mg.adjncy, Mg.vwgt, Mg.vsize, Mg.adjwgt, Mg.nparts, Mg.tpwgts, Mg.ubvec, Mg.options, Mg.objval, Mg.part);

		// vertex id

		size_t id = 0;

		// For each vertex store the processor that contain the data

		auto it = gp.getVertexIterator();

		while (it.isNext())
		{
			gp.vertex(it).template get<i>() = Mg.part[id];

			++id;
			++it;
		}
	}
Пример #6
0
int do_metis_recursive_partition(network_t *network, options_t *opt, idx_t *part) {
    int ret = ORCC_OK;
    idx_t ncon = 1;
    idx_t metis_opt[METIS_NOPTIONS];
    idx_t objval;
    adjacency_list *graph, *metis_graph;
    assert(network != NULL);
    assert(opt != NULL);
    assert(part != NULL);

    print_orcc_trace(ORCC_VL_VERBOSE_1, "Applying METIS Recursive partition for mapping");

    METIS_SetDefaultOptions(metis_opt);

    graph = set_graph_from_network(network);
    metis_graph = fix_graph_for_metis(graph);

    ret = METIS_PartGraphRecursive(&metis_graph->nb_vertices, /* idx_t *nvtxs */
                                   &ncon, /*idx_t *ncon*/
                                   metis_graph->xadj, /*idx_t *xadj*/
                                   metis_graph->adjncy, /*idx_t *adjncy*/
                                   metis_graph->vwgt, /*idx_t *vwgt*/
                                   NULL, /*idx_t *vsize*/
                                   metis_graph->adjwgt, /*idx_t *adjwgt*/
                                   &opt->nb_processors, /*idx_t *nparts*/
                                   NULL, /*real t *tpwgts*/
                                   NULL, /*real t ubvec*/
                                   metis_opt, /*idx_t *options*/
                                   &objval, /*idx_t *objval*/
                                   part); /*idx_t *part*/
    check_metis_error(ret);

    print_orcc_trace(ORCC_VL_VERBOSE_2, "METIS Edgecut : %d", objval);

    delete_graph(graph);
    delete_graph(metis_graph);
    return ret;
}
Пример #7
0
	void decompose()
	{
		if (Mg.nparts[0] != 1)
		{
			// Decompose
			METIS_PartGraphRecursive(Mg.nvtxs, Mg.ncon, Mg.xadj, Mg.adjncy, Mg.vwgt, Mg.vsize, Mg.adjwgt, Mg.nparts, Mg.tpwgts, Mg.ubvec, Mg.options, Mg.objval, Mg.part);

			// vertex id

			size_t id = 0;

			// For each vertex store the processor that contain the data

			auto it = g.getVertexIterator();

			while (it.isNext())
			{
				g.vertex(it).template get<i>() = Mg.part[id];

				++id;
				++it;
			}
		}
		else
		{
			// Trivially assign all the domains to the processor 0

			auto it = g.getVertexIterator();

			while (it.isNext())
			{
				g.vertex(it).template get<i>() = 0;

				++it;
			}
		}
	}
Пример #8
0
void METIS_PARTGRAPHRECURSIVE(int *nvtxs, idxtype *xadj, idxtype *adjncy, idxtype *vwgt, idxtype *adjwgt, int *wgtflag, int *numflag, int *nparts, int *options, int *edgecut, idxtype *part)
{
  METIS_PartGraphRecursive(nvtxs, xadj, adjncy, vwgt, adjwgt, wgtflag, numflag, nparts, options, edgecut, part);
}
Пример #9
0
void metis_partgraphrecursive__(int *nvtxs, idxtype *xadj, idxtype *adjncy, idxtype *vwgt, idxtype *adjwgt, int *wgtflag, int *numflag, int *nparts, int *options, int *edgecut, idxtype *part)
{
  METIS_PartGraphRecursive(nvtxs, xadj, adjncy, vwgt, adjwgt, wgtflag, numflag, nparts, options, edgecut, part);
}
Пример #10
0
int main()
{

  /* We aim to partition the following mesh into 4 parts:
   *  
   *  0---1---2---3---4
   *  |   |   |   |   |
   *  5---6---7---8---9
   *  |   |   |   |   |
   * 10--11--12--13--14
   *
   */
  const int nVertices = 15;
  const int nNeighs   = 44;
  idx_t xadj [nVertices+1] = { 0, 2, 5, 8, 11, 13, 16, 20, 24, 28, 31, 33, 36, 39, 42, 44 };
  idx_t adjncy [nNeighs] = { 1, 5, 0, 2, 6, 1, 3, 7, 2, 4, 8, 3, 9, 0, 6, 10, 1, 5, 7, 11,
		    2, 6, 8, 12, 3, 7, 9, 13, 4, 8, 14, 5, 11, 6, 10, 12, 7, 11,
		    13, 8, 12, 14, 9, 13 };

  std::cout << "Before Partitioning:" << std::endl;
  std::cout << std::endl;
  std::cout << "0---0---0---0---0" << std::endl;
  std::cout << "|   |   |   |   |" << std::endl;
  std::cout << "0---0---0---0---0" << std::endl;
  std::cout << "|   |   |   |   |" << std::endl;
  std::cout << "0---0---0---0---0" << std::endl;
  std::cout << std::endl;

  // partition the graph using metis
  idx_t nvtxs    = nVertices;         // number of vertices
  idx_t ncon     = 1;                 // number of balancing constraints
  idx_t *vwgt    = NULL;              // vertex weights
  idx_t *vsize   = NULL;              // vertex sizes
  idx_t *adjwgt  = NULL;              // edge weights
  idx_t nparts   = 4;                 // number of partitions
  real_t *tpwgts = NULL;              // target partition weight
  real_t *ubvec  = NULL;              // load balance tolerance for each constraint
  idx_t options[METIS_NOPTIONS];      // array of options
  METIS_SetDefaultOptions( options ); // use defaults
  idx_t objval;                       // edge-cut on return
  std::vector< idx_t > colors( nVertices, 0 ); // ranks
  
  int ierr = METIS_PartGraphRecursive( &nvtxs, &ncon, &xadj[0], &adjncy[0], vwgt, vsize,
				       adjwgt, &nparts, tpwgts, ubvec, options, &objval, &colors[0] );

  if ( ierr != METIS_OK )
    throw std::runtime_error( "METIS graph partitioning failed!" );
    
  std::cout << "After Partitioning:" << std::endl;
  std::cout << std::endl;
  std::cout << colors[0] << "---" << colors[1] << "---" << colors[2] <<
    "---" << colors[3] << "---" << colors[4] << std::endl;
  std::cout << "|   |   |   |   |" << std::endl;
  std::cout << colors[5] << "---" << colors[6] << "---" << colors[7] <<
    "---" << colors[8] << "---" << colors[9] << std::endl;
  std::cout << "|   |   |   |   |" << std::endl;
  std::cout << colors[10] << "---" << colors[11] << "---" << colors[12] <<
    "---" << colors[13] << "---" << colors[14] << std::endl;
  std::cout << std::endl;
  
  return 0;
}
Пример #11
0
JNIEXPORT jint JNICALL Java_jprime_JMetis_PartitionGraph(
		JNIEnv * env,
		jobject obj,
		jboolean j_force_PartGraphRecursive,
		jboolean j_force_PartGraphKway,
		jint j_num_vertices,
		jintArray j_xadj,
		jintArray j_adjncy,
		jintArray j_vwgt,
		jintArray j_adjwgt,
		jint j_wgtflag,
		jint j_nparts,
		jintArray j_options,
		jintArray j_partioned_nodes) {
	mysrand(7654321L);
	//delcare vars
	jint * xadj=NULL, * adjncy=NULL,* vwgt=NULL, * adjwgt=NULL, * options=NULL, * partioned_nodes=NULL;
	int idx, edges_cut=-1, num_vertices=0, nparts=0, wgtflag=0, numflag=0;
	jsize xadj_len, adjncy_len, vwgt_len, adjwgt_len, options_len, partioned_nodes_len;

	//copy the jsize vars
	num_vertices=j_num_vertices;
	nparts=j_nparts;
	wgtflag=j_wgtflag;

	//get array lengths
	xadj_len            = (*env)->GetArrayLength(env,j_xadj);
	adjncy_len          = (*env)->GetArrayLength(env,j_adjncy);
	vwgt_len            = (*env)->GetArrayLength(env,j_vwgt);
	adjwgt_len          = (*env)->GetArrayLength(env,j_adjwgt);
	options_len         = (*env)->GetArrayLength(env,j_options);
	partioned_nodes_len = (*env)->GetArrayLength(env,j_partioned_nodes);
	//printf("xadj_len=%i, adjncy_len=%i, vwgt_len=%i, adjwgt_len=%i, options_len=%i, partioned_nodes_len=%i\n",xadj_len, adjncy_len, vwgt_len, adjwgt_len, options_len, partioned_nodes_len);

	//create/get local copies
	xadj                      = (*env)->GetIntArrayElements(env,j_xadj,0);
	adjncy                    = (*env)->GetIntArrayElements(env,j_adjncy,0);
	if(vwgt_len>0)    vwgt    = (*env)->GetIntArrayElements(env,j_vwgt,0);
	if(adjwgt_len>0)  adjwgt  = (*env)->GetIntArrayElements(env,j_adjwgt,0);
	if(options_len>0) options = (*env)->GetIntArrayElements(env,j_options,0);
	partioned_nodes           = (int*)malloc(sizeof(int)*partioned_nodes_len);
#if 0
	printf("num_vertices=%i,wgtflag=%i, numflag=%i, nparts=%i\n", num_vertices, wgtflag, numflag, nparts);
	printf("xadj=%p, adjncy=%p, vwgt=%p, adjwgt=%p, options=%p, partioned_nodes=%p\n",
		xadj,
		adjncy,
		vwgt,
		adjwgt,
		options,
		partioned_nodes);
	printf("xadj:");
	for(idx=0;idx<xadj_len;idx++) {
		printf("%i ",xadj[idx]);
	}
	printf("\n");

	printf("adjncy:");
	for(idx=0;idx<adjncy_len;idx++) {
		printf("%i ",adjncy[idx]);
	}
	printf("\n");
#endif
	//call func
	if((j_nparts<8 || j_force_PartGraphRecursive) && !j_force_PartGraphKway) {
		METIS_PartGraphRecursive(
				&num_vertices,
				xadj,
				adjncy,
				vwgt,
				adjwgt,
				&wgtflag,
				&numflag,
				&nparts,
				options,
				&edges_cut,
				partioned_nodes);
	}
	else {
		METIS_PartGraphKway(
				&num_vertices,
				xadj,
				adjncy,
				vwgt,
				adjwgt,
				&wgtflag,
				&numflag,
				&nparts,
				options,
				&edges_cut,
				partioned_nodes);
	}

	//pop partioned_nodes
	(*env)->SetIntArrayRegion(env,j_partioned_nodes,0,partioned_nodes_len,partioned_nodes);

	//free local copies
	free(partioned_nodes);
	(*env)->ReleaseIntArrayElements(env, j_xadj, xadj, 0);
	(*env)->ReleaseIntArrayElements(env, j_adjncy, adjncy, 0);
	if(vwgt_len>0) (*env)->ReleaseIntArrayElements(env, j_vwgt, vwgt, 0);
	if(adjwgt_len>0) (*env)->ReleaseIntArrayElements(env, j_adjwgt, adjwgt, 0);
	if(options_len>0) (*env)->ReleaseIntArrayElements(env, j_options, options, 0);
	return edges_cut;
}
Пример #12
0
/*************************************************************************
* Let the game begin
**************************************************************************/
main(int argc, char *argv[])
{
    int i, nparts, options[10];
    idxtype *part;
    float lbvec[MAXNCON];
    GraphType graph;
    char filename[256];
    int numflag = 0, wgtflag = 0, edgecut;
    timer TOTALTmr, METISTmr, IOTmr;


    if (argc != 3) {
        printf("Usage: %s <GraphFile> <Nparts>\n",argv[0]);
        exit(0);
    }

    strcpy(filename, argv[1]);
    nparts = atoi(argv[2]);

    if (nparts < 2) {
        printf("The number of partitions should be greater than 1!\n");
        exit(0);
    }

    cleartimer(TOTALTmr);
    cleartimer(METISTmr);
    cleartimer(IOTmr);

    starttimer(TOTALTmr);
    starttimer(IOTmr);
    ReadGraph(&graph, filename, &wgtflag);
    if (graph.nvtxs <= 0) {
        printf("Empty graph. Nothing to do.\n");
        exit(0);
    }
    stoptimer(IOTmr);

    printf("**********************************************************************\n");
    printf("%s", METISTITLE);
    printf("Graph Information ---------------------------------------------------\n");
    printf("  Name: %s, #Vertices: %d, #Edges: %d, #Parts: %d\n", filename, graph.nvtxs, graph.nedges/2, nparts);
    if (graph.ncon > 1)
        printf("  Balancing Constraints: %d\n", graph.ncon);
    printf("\nRecursive Partitioning... -------------------------------------------\n");

    part = idxmalloc(graph.nvtxs, "main: part");
    options[0] = 0;

    starttimer(METISTmr);
    if (graph.ncon == 1) {
        METIS_PartGraphRecursive(&graph.nvtxs, graph.xadj, graph.adjncy, graph.vwgt, graph.adjwgt,
                                 &wgtflag, &numflag, &nparts, options, &edgecut, part);
    }
    else {
        METIS_mCPartGraphRecursive(&graph.nvtxs, &graph.ncon, graph.xadj, graph.adjncy, graph.vwgt,
                                   graph.adjwgt, &wgtflag, &numflag, &nparts, options, &edgecut, part);
    }

    stoptimer(METISTmr);

    ComputePartitionBalance(&graph, nparts, part, lbvec);

    printf("  %d-way Edge-Cut: %7d, Balance: ", nparts, edgecut);
    for (i=0; i<graph.ncon; i++)
        printf("%5.2f ", lbvec[i]);
    printf("\n");


    starttimer(IOTmr);
    WritePartition(filename, part, graph.nvtxs, nparts);
    stoptimer(IOTmr);
    stoptimer(TOTALTmr);

    printf("\nTiming Information --------------------------------------------------\n");
    printf("  I/O:          \t\t %7.3f\n", gettimer(IOTmr));
    printf("  Partitioning: \t\t %7.3f   (PMETIS time)\n", gettimer(METISTmr));
    printf("  Total:        \t\t %7.3f\n", gettimer(TOTALTmr));
    printf("**********************************************************************\n");


    GKfree(&graph.xadj, &graph.adjncy, &graph.vwgt, &graph.adjwgt, &part, LTERM);
}
Пример #13
0
idx_t* gpmetis( int argc, char **argv )
/*************************************************************************/
/*! Let the game begin! */
/*************************************************************************/
//int main(int argc, char *argv[])
{
  idx_t i;
  char *curptr, *newptr;
  idx_t options[METIS_NOPTIONS];
  graph_t *graph;
  idx_t *part;
  idx_t objval;
  params_t *params;
  int status=0;

  gk_optind = 0;

  //printf( "argc: %d\n", argc );
  //printf( "gk_optind %d\n", gk_optind );
  fflush( stdout );

    for( i = 0; i < argc; i++ )
    {
        //printf( "%s*\n", argv[ i ] );
    }


  params = parse_cmdline(argc, argv);
  //printf( "gk_optind %d\n", gk_optind );
  //fflush( stdout );
  //return NULL;

  gk_startcputimer(params->iotimer);
  graph = ReadGraph(params);

  ReadTPwgts(params, graph->ncon);
  gk_stopcputimer(params->iotimer);

  /* Check if the graph is contiguous */
  if (params->contig && !IsConnected(graph, 0)) {
    printf("***The input graph is not contiguous.\n"
           "***The specified -contig option will be ignored.\n");
    params->contig = 0;
  }

  /* Get ubvec if supplied */
  if (params->ubvecstr) {
    params->ubvec = rmalloc(graph->ncon, "main");
    curptr = params->ubvecstr;
    for (i=0; i<graph->ncon; i++) {
      params->ubvec[i] = strtoreal(curptr, &newptr);
      if (curptr == newptr)
        errexit("Error parsing entry #%"PRIDX" of ubvec [%s] (possibly missing).\n",
            i, params->ubvecstr);
      curptr = newptr;
    }
  }

  /* Setup iptype */
  if (params->iptype == -1) {
    if (params->ptype == METIS_PTYPE_RB) {
      if (graph->ncon == 1)
        params->iptype = METIS_IPTYPE_GROW;
      else
        params->iptype = METIS_IPTYPE_RANDOM;
    }
  }

  GPPrintInfo(params, graph);

  part = imalloc(graph->nvtxs, "main: part");

  METIS_SetDefaultOptions(options);
  options[METIS_OPTION_OBJTYPE] = params->objtype;
  options[METIS_OPTION_CTYPE]   = params->ctype;
  options[METIS_OPTION_IPTYPE]  = params->iptype;
  options[METIS_OPTION_RTYPE]   = params->rtype;
  options[METIS_OPTION_MINCONN] = params->minconn;
  options[METIS_OPTION_CONTIG]  = params->contig;
  options[METIS_OPTION_SEED]    = params->seed;
  options[METIS_OPTION_NITER]   = params->niter;
  options[METIS_OPTION_NCUTS]   = params->ncuts;
  options[METIS_OPTION_UFACTOR] = params->ufactor;
  options[METIS_OPTION_DBGLVL]  = params->dbglvl;

  gk_malloc_init();
  gk_startcputimer(params->parttimer);

  switch (params->ptype) {
    case METIS_PTYPE_RB:
      status = METIS_PartGraphRecursive(&graph->nvtxs, &graph->ncon, graph->xadj,
                   graph->adjncy, graph->vwgt, graph->vsize, graph->adjwgt,
                   &params->nparts, params->tpwgts, params->ubvec, options,
                   &objval, part);
      break;

    case METIS_PTYPE_KWAY:
      status = METIS_PartGraphKway(&graph->nvtxs, &graph->ncon, graph->xadj,
                   graph->adjncy, graph->vwgt, graph->vsize, graph->adjwgt,
                   &params->nparts, params->tpwgts, params->ubvec, options,
                   &objval, part);
      break;

  }

  gk_stopcputimer(params->parttimer);

  if (gk_GetCurMemoryUsed() != 0)
    printf("***It seems that Metis did not free all of its memory! Report this.\n");
  params->maxmemory = gk_GetMaxMemoryUsed();
  gk_malloc_cleanup(0);


  if (status != METIS_OK) {
    printf("\n***Metis returned with an error.\n");
  }
  else {
    if (!params->nooutput) {
      /* Write the solution */
      gk_startcputimer(params->iotimer);
      WritePartition(params->filename, part, graph->nvtxs, params->nparts);
      gk_stopcputimer(params->iotimer);
    }

    GPReportResults(params, graph, part, objval);
  }

  idx_t *r_part = ( idx_t* ) calloc( graph->nvtxs, sizeof( idx_t ) );

  for( i = 0; i < graph->nvtxs; i++ )
  {
       r_part[ i ] = part[ i ];
  }

  FreeGraph(&graph);
  gk_free((void **)&part, LTERM);
  gk_free((void **)&params->filename, &params->tpwgtsfile, &params->tpwgts,
      &params->ubvecstr, &params->ubvec, &params, LTERM);

  return r_part;
}
Пример #14
0
void MetisLB::work(LDStats* stats)
{
  /** ========================== INITIALIZATION ============================= */
  ProcArray *parr = new ProcArray(stats);
  ObjGraph *ogr = new ObjGraph(stats);

  /** ============================= STRATEGY ================================ */
  if (_lb_args.debug() >= 2) {
    CkPrintf("[%d] In MetisLB Strategy...\n", CkMyPe());
  }

  // convert ObjGraph to the adjacency structure
  int numVertices = ogr->vertices.size();	// number of vertices
  int numEdges = 0;				// number of edges

  double maxLoad = 0.0;
  int i, j, k, vert;

  /** remove duplicate edges from recvFrom */
  for(i = 0; i < numVertices; i++) {
    for(j = 0; j < ogr->vertices[i].sendToList.size(); j++) {
      vert = ogr->vertices[i].sendToList[j].getNeighborId();
      for(k = 0; k < ogr->vertices[i].recvFromList.size(); k++) {
	if(ogr->vertices[i].recvFromList[k].getNeighborId() == vert) {
	  ogr->vertices[i].sendToList[j].setNumBytes(ogr->vertices[i].sendToList[j].getNumBytes() + ogr->vertices[i].recvFromList[k].getNumBytes());
	  ogr->vertices[i].recvFromList.erase(ogr->vertices[i].recvFromList.begin() + k);
        }
      }
    }
  }

  /** the object load is normalized to an integer between 0 and 256 */
  for(i = 0; i < numVertices; i++) {
    if(ogr->vertices[i].getVertexLoad() > maxLoad)
      maxLoad = ogr->vertices[i].getVertexLoad();
    numEdges = numEdges + ogr->vertices[i].sendToList.size() + ogr->vertices[i].recvFromList.size();
  }

  /* adjacency list */
  idx_t *xadj = new idx_t[numVertices + 1];
  /* id of the neighbors */
  idx_t *adjncy = new idx_t[numEdges];
  /* weights of the vertices */
  idx_t *vwgt = new idx_t[numVertices];
  /* weights of the edges */
  idx_t *adjwgt = new idx_t[numEdges];

  int edgeNum = 0;
  double ratio = 256.0/maxLoad;

  for(i = 0; i < numVertices; i++) {
    xadj[i] = edgeNum;
    vwgt[i] = (int)ceil(ogr->vertices[i].getVertexLoad() * ratio);
    for(j = 0; j < ogr->vertices[i].sendToList.size(); j++) {
      adjncy[edgeNum] = ogr->vertices[i].sendToList[j].getNeighborId();
      adjwgt[edgeNum] = ogr->vertices[i].sendToList[j].getNumBytes();
      edgeNum++;
    }
    for(j = 0; j < ogr->vertices[i].recvFromList.size(); j++) {
      adjncy[edgeNum] = ogr->vertices[i].recvFromList[j].getNeighborId();
      adjwgt[edgeNum] = ogr->vertices[i].recvFromList[j].getNumBytes();
      edgeNum++;
    }
  }
  xadj[i] = edgeNum;
  CkAssert(edgeNum == numEdges);

  idx_t edgecut;		// number of edges cut by the partitioning
  idx_t *pemap;

  idx_t options[METIS_NOPTIONS];
  METIS_SetDefaultOptions(options);
  //options[METIS_OPTION_PTYPE] = METIS_PTYPE_RB;
  // C style numbering
  options[METIS_OPTION_NUMBERING] = 0;

  // number of constrains
  idx_t ncon = 1;
  // number of partitions
  idx_t numPes = parr->procs.size();
  real_t ubvec[ncon];
  // allow 10% imbalance
  ubvec[0] = 1.1;

  // mapping of objs to partitions
  pemap = new idx_t[numVertices];

  // Specifies size of vertices for computing the total communication volume
  idx_t *vsize = NULL;
  // This array of size nparts specifies the desired weight for each partition
  // and setting it to NULL indicates graph should be equally divided among
  // partitions
  real_t *tpwgts = NULL;

  int option = 0;
  if (WEIGHTED == option) {
    // set up the different weights between 0 and 1
    tpwgts = new real_t[numPes];
    for (i = 0; i < numPes; i++) {
      tpwgts[i] = 1.0/(real_t)numPes;
    }
  } else if (MULTI_CONSTRAINT == option) {
    CkAbort("Multiple constraints not implemented.\n");
  }

  // numVertices: num vertices in the graph; ncon: num balancing constrains
  // xadj, adjncy: of size n+1 and adjncy of 2m, adjncy[xadj[i]] through and
  // including adjncy[xadj[i+1]-1];
  // vwgt: weight of the vertices; vsize: amt of data that needs to be sent
  // for ith vertex is vsize[i]
  // adjwght: the weight of edges; numPes: total parts
  // tpwghts: target partition weight, can pass NULL to equally divide
  // ubvec: of size ncon to indicate allowed load imbalance tolerance (> 1.0)
  // options: array of options; edgecut: stores the edgecut; pemap: mapping
  METIS_PartGraphRecursive(&numVertices, &ncon,  xadj, adjncy, vwgt, vsize, adjwgt,
      &numPes, tpwgts, ubvec, options, &edgecut, pemap);

  delete[] xadj;
  delete[] adjncy;
  delete[] vwgt;
  delete[] adjwgt;
  delete[] vsize;
  delete[] tpwgts;

  if (_lb_args.debug() >= 1) {
   CkPrintf("[%d] MetisLB done! \n", CkMyPe());
  }

  for(i = 0; i < numVertices; i++) {
    if(pemap[i] != ogr->vertices[i].getCurrentPe())
      ogr->vertices[i].setNewPe(pemap[i]);
  }

  delete[] pemap;

  /** ============================== CLEANUP ================================ */
  ogr->convertDecisions(stats);
  delete parr;
  delete ogr;
}
Пример #15
0
/**************************************************************************
** This takes objects and partitions them into clusters.
*/
void GridMetisLB::Partition_Objects_Into_Clusters (CentralLB::LDStats *stats)
{
  int num_migratable_objects;
  int *migratable_objects;
  int index;
  int num_partitions;
  int *partition_to_cluster_map;
  int cluster;
  int partition;
  int partition_count;
  int *vertex_weights;
  int vertex;
  int **communication_matrix;
  LDCommData *com_data;
  int send_object;
  int recv_object;
  int send_index;
  int recv_index;
  LDObjKey *recv_objects;
  int num_objects;
  int *xadj;
  int num_edges;
  int *adjncy;
  int *edge_weights;
  int count;
  int weight_flag;
  int numbering_flag;
  int options[5];
  int edgecut;
  int *newmap;
  int i;
  int j;


  if (Num_Clusters == 1) {
    for (i = 0; i < Num_Objects; i++) {
      (&Object_Data[i])->cluster = 0;
    }

    return;
  }

  for (i = 0; i < Num_Objects; i++) {
    (&Object_Data[i])->secondary_index = -1;
  }

  // Count the number of migratable objects, which are the only candidates to give to Metis.
  // (The non-migratable objects have been placed onto the correct destination PEs earlier.)
  // After getting the count, create a migratable_objects[] array to keep track of them.
  num_migratable_objects = 0;
  for (i = 0; i < Num_Objects; i++) {
    if ((&Object_Data[i])->migratable) {
      num_migratable_objects += 1;
    }
  }

  migratable_objects = new int[num_migratable_objects];

  index = 0;
  for (i = 0; i < Num_Objects; i++) {
    if ((&Object_Data[i])->migratable) {
      (&Object_Data[i])->secondary_index = index;
      migratable_objects[index] = i;
      index += 1;
    }
  }

  // Compute the number of partitions for Metis, based on the scaled CPU power for each cluster.
  // Also create a partition-to-cluster mapping so the output of Metis can be mapped back to clusters.
  num_partitions = 0;
  for (i = 0; i < Num_Clusters; i++) {
    num_partitions += (int) ceil ((&Cluster_Data[i])->scaled_cpu_power);
  }

  partition_to_cluster_map = new int[num_partitions];

  cluster = 0;
  partition = 0;
  while (partition < num_partitions) {
    partition_count = (int) ceil ((&Cluster_Data[cluster])->scaled_cpu_power);

    for (i = partition; i < (partition + partition_count); i++) {
      partition_to_cluster_map[i] = cluster;
    }

    partition += partition_count;
    cluster += 1;
  }

  if (CK_LDB_GridMetisLB_Mode == 1) {
    vertex_weights = new int[num_migratable_objects];
    vertex = 0;
    for (i = 0; i < Num_Objects; i++) {
      if ((&Object_Data[i])->migratable) {
	vertex_weights[vertex] = (int) ceil ((&Object_Data[i])->load * 10000);
	vertex += 1;
      }
    }
  }

  // Create communication_matrix[] to hold all object-to-object message counts.
  communication_matrix = new int *[num_migratable_objects];
  for (i = 0; i < num_migratable_objects; i++) {
    communication_matrix[i] = new int[num_migratable_objects];
    for (j = 0; j < num_migratable_objects; j++) {
      communication_matrix[i][j] = 0;
    }
  }

  for (i = 0; i < stats->n_comm; i++) {
    com_data = &(stats->commData[i]);
    if ((!com_data->from_proc()) && (com_data->recv_type() == LD_OBJ_MSG)) {
      send_object = stats->getHash (com_data->sender);
      recv_object = stats->getHash (com_data->receiver.get_destObj());

      //if ((recv_object == -1) && (stats->complete_flag == 0)) {
      if ((send_object < 0) || (send_object > Num_Objects) || (recv_object < 0) || (recv_object > Num_Objects)) {
	continue;
      }

      if ((!(&Object_Data[send_object])->migratable) || (!(&Object_Data[recv_object])->migratable)) {
	continue;
      }

      send_index = (&Object_Data[send_object])->secondary_index;
      recv_index = (&Object_Data[recv_object])->secondary_index;

      communication_matrix[send_index][recv_index] += com_data->messages;
      communication_matrix[recv_index][send_index] += com_data->messages;
    } else if (com_data->receiver.get_type() == LD_OBJLIST_MSG) {
      send_object = stats->getHash (com_data->sender);

      if ((send_object < 0) || (send_object > Num_Objects)) {
	continue;
      }

      if (!(&Object_Data[send_object])->migratable) {
	continue;
      }

      recv_objects = com_data->receiver.get_destObjs (num_objects);   // (num_objects is passed by reference)

      for (j = 0; j < num_objects; j++) {
	recv_object = stats->getHash (recv_objects[j]);

	//if (recv_object == -1) {
	if ((recv_object < 0) || (recv_object > Num_Objects)) {
	  continue;
	}

	if (!(&Object_Data[recv_object])->migratable) {
	  continue;
	}

	send_index = (&Object_Data[send_object])->secondary_index;
	recv_index = (&Object_Data[recv_object])->secondary_index;

	communication_matrix[send_index][recv_index] += com_data->messages;
	communication_matrix[recv_index][send_index] += com_data->messages;
      }
    }
  }

  for (i = 0; i < num_migratable_objects; i++) {
    communication_matrix[i][i] = 0;
  }

  // Construct a graph in CSR format for input to Metis.
  xadj = new int[num_migratable_objects + 1];
  num_edges = 0;
  for (i = 0; i < num_migratable_objects; i++) {
    for (j = 0; j < num_migratable_objects; j++) {
      if (communication_matrix[i][j] > 0) {
	num_edges += 1;
      }
    }
  }
  adjncy = new int[num_edges];
  edge_weights = new int[num_edges];
  count = 0;
  xadj[0] = 0;
  for (i = 0; i < num_migratable_objects; i++) {
    for (j = 0; j < num_migratable_objects; j++) {
      if (communication_matrix[i][j] > 0) {
	adjncy[count] = j;
	edge_weights[count] = communication_matrix[i][j];
	count += 1;
      }
    }
    xadj[i+1] = count;
  }

  if (CK_LDB_GridMetisLB_Mode == 0) {
    // Call Metis to partition the communication graph.
    weight_flag = 1;      // weights on edges only
    numbering_flag = 0;   // C style numbering (base 0)
    options[0] = 0;
    newmap = new int[num_migratable_objects];

    METIS_PartGraphRecursive (&num_migratable_objects, xadj, adjncy, NULL, edge_weights, &weight_flag, &numbering_flag, &num_partitions, options, &edgecut, newmap);
  } else if (CK_LDB_GridMetisLB_Mode == 1) {
    // Call Metis to partition the communication graph.
    weight_flag = 3;      // weights on both vertices and edges
    numbering_flag = 0;   // C style numbering (base 0)
    options[0] = 0;
    newmap = new int[num_migratable_objects];

    METIS_PartGraphRecursive (&num_migratable_objects, xadj, adjncy, vertex_weights, edge_weights, &weight_flag, &numbering_flag, &num_partitions, options, &edgecut, newmap);
  } else {
    if (_lb_args.debug() > 0) {
      CkPrintf ("[%d] GridMetisLB was told to use bad mode (%d).\n", CkMyPe(), CK_LDB_GridMetisLB_Mode);
    }
  }

  // Place the partitioned objects into their correct clusters.
  for (i = 0; i < num_migratable_objects; i++) {
    partition = newmap[i];
    cluster = partition_to_cluster_map[partition];

    index = migratable_objects[i];

    (&Object_Data[index])->cluster = cluster;
  }

  // Free memory.
  delete [] newmap;
  delete [] edge_weights;
  delete [] adjncy;
  delete [] xadj;
  for (i = 0; i < num_migratable_objects; i++) {
    delete [] communication_matrix[i];
  }
  delete [] communication_matrix;
  if (CK_LDB_GridMetisLB_Mode == 1) {
    delete [] vertex_weights;
  }
  delete [] partition_to_cluster_map;
  delete [] migratable_objects;
}
Пример #16
0
/*************************************************************************
* This function partitions a finite element mesh by partitioning its nodal
* graph using KMETIS and then assigning elements in a load balanced fashion.
**************************************************************************/
int METIS_PartMeshNodal(idx_t *ne, idx_t *nn, idx_t *eptr, idx_t *eind, 
          idx_t *vwgt, idx_t *vsize, idx_t *nparts, real_t *tpwgts, 
          idx_t *options, idx_t *objval, idx_t *epart, idx_t *npart)
{
  int sigrval=0, renumber=0, ptype;
  idx_t *xadj=NULL, *adjncy=NULL;
  idx_t ncon=1, pnumflag=0;
  int rstatus=METIS_OK;

  /* set up malloc cleaning code and signal catchers */
  if (!gk_malloc_init()) 
    return METIS_ERROR_MEMORY;

  gk_sigtrap();

  if ((sigrval = gk_sigcatch()) != 0) 
    goto SIGTHROW;

  renumber = GETOPTION(options, METIS_OPTION_NUMBERING, 0);
  ptype    = GETOPTION(options, METIS_OPTION_PTYPE, METIS_PTYPE_KWAY);

  /* renumber the mesh */
  if (renumber) {
    ChangeMesh2CNumbering(*ne, eptr, eind);
    options[METIS_OPTION_NUMBERING] = 0;
  }

  /* get the nodal graph */
  rstatus = METIS_MeshToNodal(ne, nn, eptr, eind, &pnumflag, &xadj, &adjncy);
  if (rstatus != METIS_OK)
    raise(SIGERR);

  /* partition the graph */
  if (ptype == METIS_PTYPE_KWAY) 
    rstatus = METIS_PartGraphKway(nn, &ncon, xadj, adjncy, vwgt, vsize, NULL, 
                  nparts, tpwgts, NULL, options, objval, npart);
  else 
    rstatus = METIS_PartGraphRecursive(nn, &ncon, xadj, adjncy, vwgt, vsize, NULL, 
                  nparts, tpwgts, NULL, options, objval, npart);

  if (rstatus != METIS_OK)
    raise(SIGERR);

  /* partition the other side of the mesh */
  InduceRowPartFromColumnPart(*ne, eptr, eind, epart, npart, *nparts, tpwgts);


SIGTHROW:
  if (renumber) {
    ChangeMesh2FNumbering2(*ne, *nn, eptr, eind, epart, npart);
    options[METIS_OPTION_NUMBERING] = 1;
  }

  METIS_Free(xadj);
  METIS_Free(adjncy);

  gk_siguntrap();
  gk_malloc_cleanup(0);

  return metis_rcode(sigrval);
}
Пример #17
0
int MESH_PartitionWithMetis(Mesh_ptr mesh, int nparts, int **part) {

  MEdge_ptr fedge;
  MFace_ptr mf, oppf, rface;
  MRegion_ptr mr, oppr;
  List_ptr fedges, efaces, rfaces, fregions;
  int  i, ncells, ipos;
  int  nv, ne, nf, nr, nfe, nef, nfr, nrf, idx, idx2;
#ifdef METIS_5
  idx_t ngraphvtx, numflag, nedgecut, numparts, ncons;
  idx_t wtflag, metisopts[METIS_NOPTIONS];
  idx_t *vsize, *idxpart;
  idx_t  *xadj, *adjncy, *vwgt, *adjwgt;
  real_t *tpwgts, *ubvec;
#else
  idxtype ngraphvtx, numflag, nedgecut, numparts;
  idxtype  wtflag, metisopts[5] = {0,0,0,0,0};
  idxtype  *xadj, *adjncy, *vwgt, *adjwgt, *idxpart;
#endif
  

  /* First build a nodal graph of the mesh in the format required by
     metis */

  nv = MESH_Num_Vertices(mesh);
  ne = MESH_Num_Edges(mesh);
  nf = MESH_Num_Faces(mesh);
  nr = MESH_Num_Regions(mesh);

  ipos = 0;
  
  if (nr == 0) {
    
    if (nf == 0) {
      fprintf(stderr,"Cannot partition wire meshes\n");
      exit(-1);
    }

#ifdef METIS_5
    xadj = (idx_t *) malloc((nf+1)*sizeof(idx_t));
    adjncy = (idx_t *) malloc(2*ne*sizeof(idx_t));
#else    
    xadj = (idxtype *) malloc((nf+1)*sizeof(idxtype));
    adjncy = (idxtype *) malloc(2*ne*sizeof(idxtype));
#endif
    ncells = nf;

    /* Surface mesh */

    idx = 0; i = 0;
    xadj[i] = ipos;
    while ((mf = MESH_Next_Face(mesh,&idx))) {
      
      fedges = MF_Edges(mf,1,0);
      nfe = List_Num_Entries(fedges);
      
      idx2 = 0;
      while ((fedge = List_Next_Entry(fedges,&idx2))) {
	
	efaces = ME_Faces(fedge);
	nef = List_Num_Entries(efaces);
	
	if (nef == 1) {
	  continue;          /* boundary edge; nothing to do */
	}
	else {
          int j;
          for (j = 0; j < nef; j++) {
            oppf = List_Entry(efaces,j);
            if (oppf != mf) {
              adjncy[ipos] = MF_ID(oppf)-1;
              ipos++;
            }
          }
	}
	
	List_Delete(efaces);
	
      }
      
      List_Delete(fedges);
      
      i++;
      xadj[i] = ipos;
    }

  }
  else {

#ifdef METIS_5
    xadj = (idx_t *) malloc((nr+1)*sizeof(idx_t));
    adjncy = (idx_t *) malloc(2*nf*sizeof(idx_t));
#else
    xadj = (idxtype *) malloc((nr+1)*sizeof(idxtype));
    adjncy = (idxtype *) malloc(2*nf*sizeof(idxtype));
#endif
    ncells = nr;

    /* Volume mesh */

    idx = 0; i = 0;
    xadj[i] = ipos;
    while ((mr = MESH_Next_Region(mesh,&idx))) {
      
      rfaces = MR_Faces(mr);
      nrf = List_Num_Entries(rfaces);
      
      idx2 = 0;
      while ((rface = List_Next_Entry(rfaces,&idx2))) {
	
	fregions = MF_Regions(rface);
	nfr = List_Num_Entries(fregions);
	
	if (nfr > 1) {
	  oppr = List_Entry(fregions,0);
	  if (oppr == mr)
	    oppr = List_Entry(fregions,1);
	  
	  adjncy[ipos] = MR_ID(oppr)-1;
	  ipos++;
	}
        List_Delete(fregions);	
	
      }
      
      List_Delete(rfaces);
      
      i++;
      xadj[i] = ipos;
    }

  }
  


  /* Partition the graph */
  
  wtflag = 0;        /* No weights are specified */
  vwgt = adjwgt = NULL;

  numflag = 0;    /* C style numbering of elements (nodes of the dual graph) */
  ngraphvtx = ncells; /* we want the variable to be of type idxtype or idx_t */
  numparts = nparts;  /* we want the variable to be of type idxtype or idx_t */

#ifdef METIS_5
  idxpart = (idx_t *) malloc(ncells*sizeof(idx_t));

  ncons = 1;  /* Number of constraints */
  vsize = NULL;  
  tpwgts = NULL;
  ubvec = NULL;

  METIS_SetDefaultOptions(metisopts);
  metisopts[METIS_OPTION_NUMBERING] = 0;

  if (nparts <= 8)
    METIS_PartGraphRecursive(&ngraphvtx,&ncons,xadj,adjncy,vwgt,vsize,adjwgt,
			     &numparts,tpwgts,ubvec,metisopts,&nedgecut,
                             idxpart);
  else
    METIS_PartGraphKway(&ngraphvtx,&ncons,xadj,adjncy,vwgt,vsize,adjwgt,
                        &numparts,tpwgts,ubvec,metisopts,&nedgecut,idxpart);

#else

  idxpart = (idxtype *) malloc(ncells*sizeof(idxtype));

  if (nparts <= 8)
    METIS_PartGraphRecursive(&ngraphvtx,xadj,adjncy,vwgt,adjwgt,&wtflag,
			     &numflag,&numparts,metisopts,&nedgecut,idxpart);
  else
    METIS_PartGraphKway(&ngraphvtx,xadj,adjncy,vwgt,adjwgt,&wtflag,&numflag,
			&numparts,metisopts,&nedgecut,idxpart);
#endif

  free(xadj);
  free(adjncy);


  
  *part = (int *) malloc(ncells*sizeof(int));
  for (i = 0; i < ncells; i++)
    (*part)[i] = (int) idxpart[i];

  free(idxpart);
  return 1;

}
Пример #18
0
//==============================================================================
// NOTE:
// - matrix is supposed to be localized, and passes through the
// singleton filter. This means that I do not have to look
// for Dirichlet nodes (singletons). Also, all rows and columns are 
// local.
int Ifpack_METISPartitioner::ComputePartitions()
{

  int ierr;
#ifdef HAVE_IFPACK_METIS
  int nbytes = 0;
  int edgecut;
#endif

  Teuchos::RefCountPtr<Epetra_CrsGraph> SymGraph ;
  Teuchos::RefCountPtr<Epetra_Map> SymMap;
  Teuchos::RefCountPtr<Ifpack_Graph_Epetra_CrsGraph> SymIFPACKGraph;
  Teuchos::RefCountPtr<Ifpack_Graph> IFPACKGraph = Teuchos::rcp( (Ifpack_Graph*)Graph_, false );

  int Length = 2 * MaxNumEntries();
  int NumIndices;
  std::vector<int> Indices;
  Indices.resize(Length);

  /* construct the CSR graph information of the LOCAL matrix
     using the get_row function */

  std::vector<idxtype> wgtflag;
  wgtflag.resize(4);

  std::vector<int> options;
  options.resize(4);
  
  int numflag;

  if (UseSymmetricGraph_) {

#if !defined(EPETRA_NO_32BIT_GLOBAL_INDICES) || !defined(EPETRA_NO_64BIT_GLOBAL_INDICES)
    // need to build a symmetric graph. 
    // I do this in two stages:
    // 1.- construct an Epetra_CrsMatrix, symmetric
    // 2.- convert the Epetra_CrsMatrix into METIS format
    SymMap = Teuchos::rcp( new Epetra_Map(NumMyRows(),0,Graph_->Comm()) );
    SymGraph = Teuchos::rcp( new Epetra_CrsGraph(Copy,*SymMap,0) );
#endif

#ifndef EPETRA_NO_32BIT_GLOBAL_INDICES
      if(SymGraph->RowMap().GlobalIndicesInt()) {
        for (int i = 0; i < NumMyRows() ; ++i) {

          ierr = Graph_->ExtractMyRowCopy(i, Length, NumIndices, &Indices[0]);
          IFPACK_CHK_ERR(ierr);

          for (int j = 0 ; j < NumIndices ; ++j) {
            int jj = Indices[j];
            if (jj != i) {
              SymGraph->InsertGlobalIndices(i,1,&jj);
              SymGraph->InsertGlobalIndices(jj,1,&i);
            }
          }
        }
      }
      else
#endif
#ifndef EPETRA_NO_64BIT_GLOBAL_INDICES
      if(SymGraph->RowMap().GlobalIndicesLongLong()) {
        for (int i = 0; i < NumMyRows() ; ++i) {
          long long i_LL = i;

          ierr = Graph_->ExtractMyRowCopy(i, Length, NumIndices, &Indices[0]);
          IFPACK_CHK_ERR(ierr);

          for (int j = 0 ; j < NumIndices ; ++j) {
            long long jj = Indices[j];
            if (jj != i_LL) {
              SymGraph->InsertGlobalIndices(i_LL,1,&jj);
              SymGraph->InsertGlobalIndices(jj,1,&i_LL);
            }
          }
        }
      }
      else
#endif
        throw "Ifpack_METISPartitioner::ComputePartitions: GlobalIndices type unknown";

    IFPACK_CHK_ERR(SymGraph->FillComplete());
    SymIFPACKGraph = Teuchos::rcp( new Ifpack_Graph_Epetra_CrsGraph(SymGraph) );
    IFPACKGraph = SymIFPACKGraph;
  }

  // now work on IFPACKGraph, that can be the symmetric or
  // the non-symmetric one

  /* set parameters */
   
  wgtflag[0] = 0;    /* no weights */
  numflag    = 0;    /* C style */
  options[0] = 0;    /* default options */
   
  std::vector<idxtype> xadj;
  xadj.resize(NumMyRows() + 1);

  std::vector<idxtype> adjncy;
  adjncy.resize(NumMyNonzeros());
   
  int count = 0; 
  int count2 = 0; 
  xadj[0] = 0;
  
  for (int i = 0; i < NumMyRows() ; ++i) {

    xadj[count2+1] = xadj[count2]; /* nonzeros in row i-1 */

    ierr = IFPACKGraph->ExtractMyRowCopy(i, Length, NumIndices, &Indices[0]);
    IFPACK_CHK_ERR(ierr);

    for (int j = 0 ; j < NumIndices ; ++j) {
      int jj = Indices[j];
      if (jj != i) {
	adjncy[count++] = jj;
	xadj[count2+1]++;
      }
    }
    count2++;
  }

  std::vector<idxtype> NodesInSubgraph;
  NodesInSubgraph.resize(NumLocalParts_);

  // some cases can be handled separately
  
  int ok;

  if (NumLocalParts() == 1) {

    for (int i = 0 ; i < NumMyRows() ; ++i) 
      Partition_[i] = 0;
    
  } else if (NumLocalParts() == NumMyRows()) {

    for (int i = 0 ; i < NumMyRows() ; ++i) 
      Partition_[i] = i;
  
  } else {

    ok = 0;

    // sometimes METIS creates less partitions than specified.
    // ok will check this problem, and recall metis, asking
    // for NumLocalParts_/2 partitions
    while (ok == 0) {
      
      for (int i = 0 ; i < NumMyRows() ; ++i) 
	Partition_[i] = -1;
    
#ifdef HAVE_IFPACK_METIS
      int j = NumMyRows();
      if (NumLocalParts_ < 8) {

	int i = 1; /* optype in the METIS manual */
	numflag = 0;
	METIS_EstimateMemory(&j, &xadj[0], &adjncy[0], 
			     &numflag, &i, &nbytes );
	
	METIS_PartGraphRecursive(&j, &xadj[0], &adjncy[0],
				 NULL, NULL,
				 &wgtflag[0], &numflag, &NumLocalParts_, 
				 &options[0], &edgecut, &Partition_[0]);
      } else {

	numflag = 0;
	
	METIS_PartGraphKway (&j, &xadj[0], &adjncy[0], 
			     NULL, 
			     NULL, &wgtflag[0], &numflag, 
			     &NumLocalParts_, &options[0],
			     &edgecut, &Partition_[0]);
      }
#else
      numflag = numflag * 2; // avoid warning for unused variable
      if (Graph_->Comm().MyPID() == 0) {
	cerr << "METIS was not linked; now I put all" << endl;
	cerr << "the local nodes in the same partition." << endl;
      }
      for (int i = 0 ; i < NumMyRows() ; ++i) 
	Partition_[i] = 0;
      NumLocalParts_ = 1;
#endif
      
      ok = 1;
      
      for (int i = 0 ; i < NumLocalParts() ; ++i) 
	NodesInSubgraph[i] = 0;

      for (int i = 0 ; i < NumMyRows() ; ++i) {
	int j = Partition_[i];
	if ((j < 0) || (j>= NumLocalParts())) {
	  ok = 0;
	  break;
	} 
	else NodesInSubgraph[j]++;
      }
      
      for (int i = 0 ; i < NumLocalParts() ; ++i) {
	if( NodesInSubgraph[i] == 0 ) {
	  ok = 0;
	  break;
	}
      }
      
      if (ok == 0) {
	cerr << "Specified number of subgraphs ("
	     << NumLocalParts_ << ") generates empty subgraphs." << endl;
	cerr << "Now I recall METIS with NumLocalParts_ = "
	     << NumLocalParts_ / 2 << "..." << endl;
	NumLocalParts_ = NumLocalParts_/2;
      }
      
      if (NumLocalParts() == 0) {
	IFPACK_CHK_ERR(-10); // something went wrong
      }
      
      if (NumLocalParts() == 1) {
	for (int i = 0 ; i < NumMyRows() ; ++i) 
	  Partition_[i] = 0;
	ok = 1;
      }
      
    } /* while( ok == 0 ) */
  
  } /* if( NumLocalParts_ == 1 ) */

  return(0);
} 
Пример #19
0
sparse_matrix* graph_partition(LIST *list , partition_t* partition_info)
{
	graph_t* graph;
	params_t *params;
	idx_t options[METIS_NOPTIONS], status;
	idx_t objval;

	sparse_matrix* matrix = (sparse_matrix*)malloc(sizeof(sparse_matrix));

	graph = ReadGraph(list);

	params = bmalloc(sizeof(*params), "Allocating memory for params");

	METIS_SetDefaultOptions(options);
	METIS_init_params(params, graph->ncon);
	options[METIS_OPTION_OBJTYPE] = params->objtype;
	options[METIS_OPTION_CTYPE]   = params->ctype;
	options[METIS_OPTION_IPTYPE]  = params->iptype;
	options[METIS_OPTION_RTYPE]   = params->rtype;
	options[METIS_OPTION_NO2HOP]  = params->no2hop;
	options[METIS_OPTION_MINCONN] = params->minconn;
	options[METIS_OPTION_CONTIG]  = params->contig;
	options[METIS_OPTION_SEED]    = params->seed;
	options[METIS_OPTION_NITER]   = params->niter;
	options[METIS_OPTION_NCUTS]   = params->ncuts;
	options[METIS_OPTION_UFACTOR] = params->ufactor;
	options[METIS_OPTION_DBGLVL]  = params->dbglvl;

	//print_input_data(graph,params);

	params->tpwgts = NULL;
	params->ubvec = NULL;
	partition_info->partion_table = imalloc(graph->nvtxs, "Allocate memory for part");

	switch (params->ptype) {
	    case METIS_PTYPE_RB:
	      status = METIS_PartGraphRecursive(&graph->nvtxs, &graph->ncon, graph->xadj,
	                   graph->adjncy, graph->vwgt, graph->vsize, graph->adjwgt,
	                   &params->nparts, params->tpwgts, params->ubvec, options,
	                   &objval, partition_info->partion_table);
	      break;

	    case METIS_PTYPE_KWAY:
	      status = METIS_PartGraphKway(&graph->nvtxs, &graph->ncon, graph->xadj,
	                   graph->adjncy, graph->vwgt, graph->vsize, graph->adjwgt,
	                   &params->nparts, params->tpwgts, params->ubvec, options,
	                   &objval, partition_info->partion_table);
	      break;

	}
	if (status != METIS_OK) {
		fprintf(stderr,"\n***Metis returned with an error.***\n");
		return NULL;
	}
    partition_info->size = graph->nvtxs;
    partition_info->noOfParts = params->nparts;
    WritePartition(params->filename, partition_info->partion_table, graph->nvtxs, params->nparts);

	printf("Objval: %d\n",objval);

	matrix->nz = -1;
	matrix->n = graph->nvtxs;
	matrix->p = graph->xadj;
	matrix->i = graph->adjncy;
	matrix->x = NULL;


	return matrix;
}
Пример #20
0
/**************************************************************************
** This takes objects in a cluster and partitions them onto PEs.
*/
void GridMetisLB::Partition_ClusterObjects_Into_PEs (CentralLB::LDStats *stats, int cluster)
{
  int num_migratable_cluster_objects;
  int *migratable_cluster_objects;
  int index;
  int num_available_cluster_pes;
  int num_partitions;
  int *partition_to_pe_map;
  int pe;
  int partition;
  int partition_count;
  int *vertex_weights;
  int vertex;
  int **communication_matrix;
  LDCommData *com_data;
  int send_object;
  int recv_object;
  int send_index;
  int recv_index;
  LDObjKey *recv_objects;
  int num_objects;
  int *xadj;
  int num_edges;
  int *adjncy;
  int *edge_weights;
  int count;
  int weight_flag;
  int numbering_flag;
  int options[5];
  int edgecut;
  int *newmap;
  int i;
  int j;


  for (i = 0; i < Num_Objects; i++) {
    (&Object_Data[i])->secondary_index = -1;
  }

  // Count the number of migratable objects within this cluster, which are the only candidates to give to Metis.
  // (The non-migratable objects have been placed onto the correct destination PEs earlier.)
  // After getting the count, create a migratable_cluster_objects[] array to keep track of them.
  num_migratable_cluster_objects = 0;
  for (i = 0; i < Num_Objects; i++) {
    if (((&Object_Data[i])->migratable) && ((&Object_Data[i])->cluster == cluster)) {
      num_migratable_cluster_objects += 1;
    }
  }

  migratable_cluster_objects = new int[num_migratable_cluster_objects];

  index = 0;
  for (i = 0; i < Num_Objects; i++) {
    if (((&Object_Data[i])->migratable) && ((&Object_Data[i])->cluster == cluster)) {
      (&Object_Data[i])->secondary_index = index;
      migratable_cluster_objects[index] = i;
      index += 1;
    }
  }

  // Count the number of available PEs in the cluster.
  num_available_cluster_pes = 0;
  for (i = 0; i < Num_PEs; i++) {
    if (((&PE_Data[i])->available) && ((&PE_Data[i])->cluster == cluster)) {
      num_available_cluster_pes += 1;
    }
  }

  // Compute the number of partitions for Metis, based on the relative speed of each PE.
  // Also create the partition-to-PE mapping so the output of Metis can be mapped back to PEs.
  num_partitions = 0;
  for (i = 0; i < Num_PEs; i++) {
    if (((&PE_Data[i])->available) && ((&PE_Data[i])->cluster == cluster)) {
      num_partitions += (int) ceil ((&PE_Data[i])->relative_speed);
    }
  }

  partition_to_pe_map = new int[num_partitions];

  pe = 0;
  while (((!(&PE_Data[pe])->available) || ((&PE_Data[pe])->cluster != cluster)) && (pe < Num_PEs)) {
    pe += 1;
  }
  if (pe >= Num_PEs) {
    CmiAbort ("GridMetisLB: Error computing partition to PE map!\n");
  }
  partition = 0;
  while (partition < num_partitions) {
    partition_count = (int) ceil ((&PE_Data[pe])->relative_speed);

    for (i = partition; i < (partition + partition_count); i++) {
      partition_to_pe_map[i] = pe;
    }

    partition += partition_count;

    pe += 1;
    while (((!(&PE_Data[pe])->available) || ((&PE_Data[pe])->cluster != cluster)) && (pe < Num_PEs)) {
      pe += 1;
    }
    if (pe > Num_PEs) {
      CmiAbort ("GridMetisLB: Error computing partition to PE map!\n");
    }
  }

  // Compute vertex weights for the objects.
  vertex_weights = new int[num_migratable_cluster_objects];
  vertex = 0;
  for (i = 0; i < Num_Objects; i++) {
    if ((&Object_Data[i])->migratable && ((&Object_Data[i])->cluster == cluster)) {
      vertex_weights[vertex] = (int) ceil ((&Object_Data[i])->load * 10000);
      vertex += 1;
    }
  }

  // Create communication_matrix[] to hold all object-to-object message counts;
  communication_matrix = new int *[num_migratable_cluster_objects];
  for (i = 0; i < num_migratable_cluster_objects; i++) {
    communication_matrix[i] = new int[num_migratable_cluster_objects];
    for (j = 0; j < num_migratable_cluster_objects; j++) {
      communication_matrix[i][j] = 0;
    }
  }

  for (i = 0; i < stats->n_comm; i++) {
    com_data = &(stats->commData[i]);
    if ((!com_data->from_proc()) && (com_data->recv_type() == LD_OBJ_MSG)) {
      send_object = stats->getHash (com_data->sender);
      recv_object = stats->getHash (com_data->receiver.get_destObj());

      //if ((recv_object == -1) && (stats->complete_flag == 0)) {
      if ((send_object < 0) || (send_object > Num_Objects) || (recv_object < 0) || (recv_object > Num_Objects)) {
	continue;
      }

      if ((!(&Object_Data[send_object])->migratable) || (!(&Object_Data[recv_object])->migratable)) {
	continue;
      }

      if (((&Object_Data[send_object])->cluster != cluster) || ((&Object_Data[recv_object])->cluster != cluster)) {
	continue;
      }

      send_index = (&Object_Data[send_object])->secondary_index;
      recv_index = (&Object_Data[recv_object])->secondary_index;

      communication_matrix[send_index][recv_index] += com_data->messages;
      communication_matrix[recv_index][send_index] += com_data->messages;
    } else if (com_data->receiver.get_type() == LD_OBJLIST_MSG) {
      send_object = stats->getHash (com_data->sender);

      if ((send_object < 0) || (send_object > Num_Objects)) {
	continue;
      }

      if (!(&Object_Data[send_object])->migratable) {
	continue;
      }

      if ((&Object_Data[send_object])->cluster != cluster) {
	continue;
      }

      recv_objects = com_data->receiver.get_destObjs (num_objects);   // (num_objects is passed by reference)

      for (j = 0; j < num_objects; j++) {
	recv_object = stats->getHash (recv_objects[j]);

	//if (recv_object == -1) {
	if ((recv_object < 0) || (recv_object > Num_Objects)) {
	  continue;
	}

	if (!(&Object_Data[recv_object])->migratable) {
	  continue;
	}

	if ((&Object_Data[recv_object])->cluster != cluster) {
	  continue;
	}

	send_index = (&Object_Data[send_object])->secondary_index;
	recv_index = (&Object_Data[recv_object])->secondary_index;

	communication_matrix[send_index][recv_index] += com_data->messages;
	communication_matrix[recv_index][send_index] += com_data->messages;
      }
    }
  }

  for (i = 0; i < num_migratable_cluster_objects; i++) {
    communication_matrix[i][i] = 0;
  }

  // Construct a graph in CSR format for input to Metis.
  xadj = new int[num_migratable_cluster_objects + 1];
  num_edges = 0;
  for (i = 0; i < num_migratable_cluster_objects; i++) {
    for (j = 0; j < num_migratable_cluster_objects; j++) {
      if (communication_matrix[i][j] > 0) {
	num_edges += 1;
      }
    }
  }
  adjncy = new int[num_edges];
  edge_weights = new int[num_edges];
  count = 0;
  xadj[0] = 0;
  for (i = 0; i < num_migratable_cluster_objects; i++) {
    for (j = 0; j < num_migratable_cluster_objects; j++) {
      if (communication_matrix[i][j] > 0) {
	adjncy[count] = j;
	edge_weights[count] = communication_matrix[i][j];
	count += 1;
      }
    }
    xadj[i+1] = count;
  }

  // Call Metis to partition the communication graph.
  weight_flag = 3;      // weights on both vertices and edges
  numbering_flag = 0;   // C style numbering (base 0)
  options[0] = 0;
  newmap = new int[num_migratable_cluster_objects];

  CmiPrintf ("[%d] GridMetisLB is partitioning %d objects in cluster %d into %d partitions.\n", CmiMyPe(), num_migratable_cluster_objects, cluster, num_partitions);

  METIS_PartGraphRecursive (&num_migratable_cluster_objects, xadj, adjncy, vertex_weights, edge_weights, &weight_flag, &numbering_flag, &num_partitions, options, &edgecut, newmap);

  // Place the partitioned objects onto their correct PEs.
  for (i = 0; i < num_migratable_cluster_objects; i++) {
    partition = newmap[i];
    pe = partition_to_pe_map[partition];

    index = migratable_cluster_objects[i];

    /* WRONG!
    for (j = 0; j < Num_Objects; j++) {
      if ((&Object_Data[j])->secondary_index == index) {
	(&Object_Data[j])->to_pe = pe;
	break;
      }
    }
    */

    (&Object_Data[index])->to_pe = pe;
  }

  // Free memory.
  delete [] newmap;
  delete [] edge_weights;
  delete [] adjncy;
  delete [] xadj;
  for (i = 0; i < num_migratable_cluster_objects; i++) {
    delete [] communication_matrix[i];
  }
  delete [] communication_matrix;
  delete [] vertex_weights;
  delete [] partition_to_pe_map;
  delete [] migratable_cluster_objects;
}
Пример #21
0
void InitKWayPartitioningRB(ctrl_t *ctrl, graph_t *graph)
{
  idx_t i, options[METIS_NOPTIONS], curobj=0;
  idx_t *bestwhere=NULL;
  real_t *ubvec=NULL;
  int status;

  METIS_SetDefaultOptions(options);
  options[METIS_OPTION_NITER]   = 10;
  options[METIS_OPTION_OBJTYPE] = METIS_OBJTYPE_CUT;
  options[METIS_OPTION_NO2HOP]  = ctrl->no2hop;
  options[METIS_OPTION_ONDISK]  = ctrl->ondisk;


  ubvec = rmalloc(graph->ncon, "InitKWayPartitioning: ubvec");
  for (i=0; i<graph->ncon; i++) 
    ubvec[i] = (real_t)pow(ctrl->ubfactors[i], 1.0/log(ctrl->nparts));


  switch (ctrl->objtype) {
    case METIS_OBJTYPE_CUT:
    case METIS_OBJTYPE_VOL:
      options[METIS_OPTION_NCUTS] = ctrl->nIparts;
      status = METIS_PartGraphRecursive(&graph->nvtxs, &graph->ncon, 
                   graph->xadj, graph->adjncy, graph->vwgt, graph->vsize, 
                   graph->adjwgt, &ctrl->nparts, ctrl->tpwgts, ubvec, 
                   options, &curobj, graph->where);

      if (status != METIS_OK)
        gk_errexit(SIGERR, "Failed during initial partitioning\n");

      break;

#ifdef XXX /* This does not seem to help */
    case METIS_OBJTYPE_VOL:
      bestwhere = imalloc(graph->nvtxs, "InitKWayPartitioning: bestwhere");
      options[METIS_OPTION_NCUTS] = 2;

      ntrials = (ctrl->nIparts+1)/2;
      for (i=0; i<ntrials; i++) {
        status = METIS_PartGraphRecursive(&graph->nvtxs, &graph->ncon, 
                     graph->xadj, graph->adjncy, graph->vwgt, graph->vsize, 
                     graph->adjwgt, &ctrl->nparts, ctrl->tpwgts, ubvec, 
                     options, &curobj, graph->where);
        if (status != METIS_OK)
          gk_errexit(SIGERR, "Failed during initial partitioning\n");

        curobj = ComputeVolume(graph, graph->where);

        if (i == 0 || bestobj > curobj) {
          bestobj = curobj;
          if (i < ntrials-1)
            icopy(graph->nvtxs, graph->where, bestwhere);
        }

        if (bestobj == 0)
          break;
      }
      if (bestobj != curobj)
        icopy(graph->nvtxs, bestwhere, graph->where);

      break;
#endif

    default:
      gk_errexit(SIGERR, "Unknown objtype: %d\n", ctrl->objtype);
  }

  gk_free((void **)&ubvec, &bestwhere, LTERM);

}
Пример #22
0
/*It uses METIS library to accomplish that*/
void TopoCentLB::computePartitions(CentralLB::LDStats *stats,int count,int *newmap)
{
	
  int numobjs = stats->n_objs;
	int i, j, m;

  // allocate space for the computing data
  double *objtime = new double[numobjs];
  int *objwt = new int[numobjs];
  int *origmap = new int[numobjs];
  LDObjHandle *handles = new LDObjHandle[numobjs];
  
	for(i=0;i<numobjs;i++) {
    objtime[i] = 0.0;
    objwt[i] = 0;
    origmap[i] = 0;
  }

  //Prepare compute loads for METIS library
  for (i=0; i<stats->n_objs; i++) {
    LDObjData &odata = stats->objData[i];
    if (!odata.migratable) 
      CmiAbort("MetisLB doesnot dupport nonmigratable object.\n");
    int frompe = stats->from_proc[i];
    origmap[i] = frompe;
    objtime[i] = odata.wallTime*stats->procs[frompe].pe_speed;
    handles[i] = odata.handle;
  }

  // to convert the weights on vertices to integers
  double max_objtime = objtime[0];
  for(i=0; i<numobjs; i++) {
    if(max_objtime < objtime[i])
      max_objtime = objtime[i];
  }
	int maxobj=0;
	int totalwt=0;
  double ratio = 1000.0/max_objtime;
  for(i=0; i<numobjs; i++) {
      objwt[i] = (int)(objtime[i]*ratio);
			if(maxobj<objwt[i])
				maxobj=objwt[i];
			totalwt+=objwt[i];
  }
	
  int **comm = new int*[numobjs];
  for (i=0; i<numobjs; i++) {
    comm[i] = new int[numobjs];
    for (j=0; j<numobjs; j++)  {
      comm[i][j] = 0;
    }
  }

  //Prepare communication for METIS library
  const int csz = stats->n_comm;
  for(i=0; i<csz; i++) {
      LDCommData &cdata = stats->commData[i];
      //if(cdata.from_proc() || cdata.receiver.get_type() != LD_OBJ_MSG)
        //continue;
			if(!cdata.from_proc() && cdata.receiver.get_type() == LD_OBJ_MSG){
      	int senderID = stats->getHash(cdata.sender);
      	int recverID = stats->getHash(cdata.receiver.get_destObj());
      	CmiAssert(senderID < numobjs);
      	CmiAssert(recverID < numobjs);
				comm[senderID][recverID] += cdata.messages;
      	comm[recverID][senderID] += cdata.messages;
				//Use bytes or messages -- do i include messages for objlist too...??
			}
			else if (cdata.receiver.get_type() == LD_OBJLIST_MSG) {
				//CkPrintf("in objlist..\n");
        int nobjs;
        LDObjKey *objs = cdata.receiver.get_destObjs(nobjs);
        int senderID = stats->getHash(cdata.sender);
        for (j=0; j<nobjs; j++) {
           int recverID = stats->getHash(objs[j]);
           if((senderID == -1)||(recverID == -1))
              if (_lb_args.migObjOnly()) continue;
              else CkAbort("Error in search\n");
           comm[senderID][recverID] += cdata.messages;
           comm[recverID][senderID] += cdata.messages;
        }
			}
		}

// ignore messages sent from an object to itself
  for (i=0; i<numobjs; i++)
    comm[i][i] = 0;

  // construct the graph in CSR format
  int *xadj = new int[numobjs+1];
  int numedges = 0;
  for(i=0;i<numobjs;i++) {
    for(j=0;j<numobjs;j++) {
      if(comm[i][j] != 0)
        numedges++;
    }
  }
  int *adjncy = new int[numedges];
  int *edgewt = new int[numedges];
	int factor = 10;
  xadj[0] = 0;
  int count4all = 0;
  for (i=0; i<numobjs; i++) {
    for (j=0; j<numobjs; j++) { 
      if (comm[i][j] != 0) { 
        adjncy[count4all] = j;
        edgewt[count4all++] = comm[i][j]/factor;
      }
    }
    xadj[i+1] = count4all;
  }

  //Call METIS routine
  int wgtflag = 3; // Weights both on vertices and edges
  int numflag = 0; // C Style numbering
  int options[5];
  int edgecut;
  options[0] = 0;

  if (count < 1) {
    CkPrintf("error: Number of Pe less than 1!");
  }
  else if (count == 1) {
   	for(m=0;m<numobjs;m++) 
			newmap[i] = origmap[i];
  }
  else {
		/*
  	if (count > 8)
			METIS_PartGraphKway(&numobjs, xadj, adjncy, objwt, edgewt, 
			    &wgtflag, &numflag, &count, options, 
			    &edgecut, newmap);
	  else
			METIS_PartGraphRecursive(&numobjs, xadj, adjncy, objwt, edgewt, 
				 &wgtflag, &numflag, &count, options, 
				 &edgecut, newmap);
		*/
	 	METIS_PartGraphRecursive(&numobjs, xadj, adjncy, objwt, edgewt,
                                 &wgtflag, &numflag, &count, options,
                                 &edgecut, newmap);
  }
	 
 
  //Debugging code: Checking load on each partition
  if(_lb_args.debug() >=2){
	  int total=0;
	  int *chkwt = new int[count];
	  for(i=0;i<count;i++)
		  chkwt[i]=0;
	  for(i=0;i<numobjs;i++){
	  	chkwt[newmap[i]] += objwt[i];
		  total += objwt[i];
	  }
	  for(i=0;i<count;i++)
		  CkPrintf("%d -- %d\n",i,chkwt[i]);
	  CkPrintf("Totalwt of all partitions after call to METIS:%d, Avg is %d\n",total,total/count);
  }

  //Clean up all the variables allocated in this routine
  for(i=0;i<numobjs;i++)
    delete[] comm[i];
  delete[] comm;
  delete[] objtime;
  delete[] xadj;
  delete[] adjncy;
  delete[] objwt;
  delete[] edgewt;
	delete[] handles;
  delete[] origmap;

}
Пример #23
0
/*************************************************************************
* 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;
}
Пример #24
0
// Call Metis with options from dictionary.
Foam::label Foam::metisDecomp::decompose
(
    const List<int>& adjncy,
    const List<int>& xadj,
    const scalarField& cWeights,

    List<int>& finalDecomp
)
{
    // C style numbering
    int numFlag = 0;

    // Method of decomposition
    // recursive: multi-level recursive bisection (default)
    // k-way: multi-level k-way
    word method("k-way");

    int numCells = xadj.size()-1;

    // decomposition options. 0 = use defaults
    List<int> options(5, 0);

    // processor weights initialised with no size, only used if specified in
    // a file
    Field<floatScalar> processorWeights;

    // cell weights (so on the vertices of the dual)
    List<int> cellWeights;

    // face weights (so on the edges of the dual)
    List<int> faceWeights;


    // Check for externally provided cellweights and if so initialise weights
    scalar minWeights = gMin(cWeights);
    if (cWeights.size() > 0)
    {
        if (minWeights <= 0)
        {
            WarningIn
            (
                "metisDecomp::decompose"
                "(const pointField&, const scalarField&)"
            )   << "Illegal minimum weight " << minWeights
                << endl;
        }

        if (cWeights.size() != numCells)
        {
            FatalErrorIn
            (
                "metisDecomp::decompose"
                "(const pointField&, const scalarField&)"
            )   << "Number of cell weights " << cWeights.size()
                << " does not equal number of cells " << numCells
                << exit(FatalError);
        }
        // Convert to integers.
        cellWeights.setSize(cWeights.size());
        forAll(cellWeights, i)
        {
            cellWeights[i] = int(cWeights[i]/minWeights);
        }
    }


    // Check for user supplied weights and decomp options
    if (decompositionDict_.found("metisCoeffs"))
    {
        const dictionary& metisCoeffs =
            decompositionDict_.subDict("metisCoeffs");
        word weightsFile;

        if (metisCoeffs.readIfPresent("method", method))
        {
            if (method != "recursive" && method != "k-way")
            {
                FatalErrorIn("metisDecomp::decompose()")
                        << "Method " << method << " in metisCoeffs in dictionary : "
                        << decompositionDict_.name()
                        << " should be 'recursive' or 'k-way'"
                        << exit(FatalError);
            }

            Info<< "metisDecomp : Using Metis method     " << method
                << nl << endl;
        }

        if (metisCoeffs.readIfPresent("options", options))
        {
            if (options.size() != 5)
            {
                FatalErrorIn("metisDecomp::decompose()")
                        << "Number of options in metisCoeffs in dictionary : "
                        << decompositionDict_.name()
                        << " should be 5"
                        << exit(FatalError);
            }

            Info<< "metisDecomp : Using Metis options     " << options
                << nl << endl;
        }

        if (metisCoeffs.readIfPresent("processorWeights", processorWeights))
        {
            processorWeights /= sum(processorWeights);

            if (processorWeights.size() != nProcessors_)
            {
                FatalErrorIn("metisDecomp::decompose(const pointField&)")
                        << "Number of processor weights "
                        << processorWeights.size()
                        << " does not equal number of domains " << nProcessors_
                        << exit(FatalError);
            }
        }

        //if (metisCoeffs.readIfPresent("cellWeightsFile", weightsFile))
        //{
        //    Info<< "metisDecomp : Using cell-based weights." << endl;
        //
        //    IOList<int> cellIOWeights
        //    (
        //        IOobject
        //        (
        //            weightsFile,
        //            mesh_.time().timeName(),
        //            mesh_,
        //            IOobject::MUST_READ,
        //            IOobject::AUTO_WRITE
        //        )
        //    );
        //    cellWeights.transfer(cellIOWeights);
        //
        //    if (cellWeights.size() != xadj.size()-1)
        //    {
        //        FatalErrorIn("metisDecomp::decompose(const pointField&)")
        //            << "Number of cell weights " << cellWeights.size()
        //            << " does not equal number of cells " << xadj.size()-1
        //            << exit(FatalError);
        //    }
        //}
    }

    int nProcs = nProcessors_;

    // output: cell -> processor addressing
    finalDecomp.setSize(numCells);

    // output: number of cut edges
    int edgeCut = 0;

    // Vertex weight info
    int wgtFlag = 0;
    int* vwgtPtr = NULL;
    int* adjwgtPtr = NULL;

    if (cellWeights.size())
    {
        vwgtPtr = cellWeights.begin();
        wgtFlag += 2;       // Weights on vertices
    }
    if (faceWeights.size())
    {
        adjwgtPtr = faceWeights.begin();
        wgtFlag += 1;       // Weights on edges
    }

    if (method == "recursive")
    {
        if (processorWeights.size())
        {
            METIS_WPartGraphRecursive
            (
                &numCells,         // num vertices in graph
                const_cast<List<int>&>(xadj).begin(),   // indexing into adjncy
                const_cast<List<int>&>(adjncy).begin(), // neighbour info
                vwgtPtr,           // vertexweights
                adjwgtPtr,         // no edgeweights
                &wgtFlag,
                &numFlag,
                &nProcs,
                processorWeights.begin(),
                options.begin(),
                &edgeCut,
                finalDecomp.begin()
            );
        }
        else
        {
            METIS_PartGraphRecursive
            (
                &numCells,         // num vertices in graph
                const_cast<List<int>&>(xadj).begin(),   // indexing into adjncy
                const_cast<List<int>&>(adjncy).begin(), // neighbour info
                vwgtPtr,           // vertexweights
                adjwgtPtr,         // no edgeweights
                &wgtFlag,
                &numFlag,
                &nProcs,
                options.begin(),
                &edgeCut,
                finalDecomp.begin()
            );
        }
    }
    else
    {
        if (processorWeights.size())
        {
            METIS_WPartGraphKway
            (
                &numCells,         // num vertices in graph
                const_cast<List<int>&>(xadj).begin(),   // indexing into adjncy
                const_cast<List<int>&>(adjncy).begin(), // neighbour info
                vwgtPtr,           // vertexweights
                adjwgtPtr,         // no edgeweights
                &wgtFlag,
                &numFlag,
                &nProcs,
                processorWeights.begin(),
                options.begin(),
                &edgeCut,
                finalDecomp.begin()
            );
        }
        else
        {
            METIS_PartGraphKway
            (
                &numCells,         // num vertices in graph
                const_cast<List<int>&>(xadj).begin(),   // indexing into adjncy
                const_cast<List<int>&>(adjncy).begin(), // neighbour info
                vwgtPtr,           // vertexweights
                adjwgtPtr,         // no edgeweights
                &wgtFlag,
                &numFlag,
                &nProcs,
                options.begin(),
                &edgeCut,
                finalDecomp.begin()
            );
        }
    }

    return edgeCut;
}
Пример #25
0
/*************************************************************************
* This function partitions a finite element mesh by partitioning its dual
* graph using KMETIS and then assigning nodes in a load balanced fashion.
**************************************************************************/
int METIS_PartMeshDual(idx_t *ne, idx_t *nn, idx_t *eptr, idx_t *eind, 
          idx_t *vwgt, idx_t *vsize, idx_t *ncommon, idx_t *nparts, 
          real_t *tpwgts, idx_t *options, idx_t *objval, idx_t *epart, 
          idx_t *npart) 
{
  int sigrval=0, renumber=0, ptype;
  idx_t i, j;
  idx_t *xadj=NULL, *adjncy=NULL, *nptr=NULL, *nind=NULL;
  idx_t ncon=1, pnumflag=0;
  int rstatus = METIS_OK;

  /* set up malloc cleaning code and signal catchers */
  if (!gk_malloc_init()) 
    return METIS_ERROR_MEMORY;

  gk_sigtrap();

  if ((sigrval = gk_sigcatch()) != 0) 
    goto SIGTHROW;

  renumber = GETOPTION(options, METIS_OPTION_NUMBERING, 0);
  ptype    = GETOPTION(options, METIS_OPTION_PTYPE, METIS_PTYPE_KWAY);

  /* renumber the mesh */
  if (renumber) {
    ChangeMesh2CNumbering(*ne, eptr, eind);
    options[METIS_OPTION_NUMBERING] = 0;
  }

  /* get the dual graph */
  rstatus = METIS_MeshToDual(ne, nn, eptr, eind, ncommon, &pnumflag, &xadj, &adjncy);
  if (rstatus != METIS_OK)
    raise(SIGERR);

  /* partition the graph */
  if (ptype == METIS_PTYPE_KWAY) 
    rstatus = METIS_PartGraphKway(ne, &ncon, xadj, adjncy, vwgt, vsize, NULL, 
                  nparts, tpwgts, NULL, options, objval, epart);
  else 
    rstatus = METIS_PartGraphRecursive(ne, &ncon, xadj, adjncy, vwgt, vsize, NULL, 
                  nparts, tpwgts, NULL, options, objval, epart);

  if (rstatus != METIS_OK)
    raise(SIGERR);


  /* construct the node-element list */
  nptr = ismalloc(*nn+1, 0, "METIS_PartMeshDual: nptr");
  nind = imalloc(eptr[*ne], "METIS_PartMeshDual: nind");

  for (i=0; i<*ne; i++) {
    for (j=eptr[i]; j<eptr[i+1]; j++)
      nptr[eind[j]]++;
  }
  MAKECSR(i, *nn, nptr);

  for (i=0; i<*ne; i++) {
    for (j=eptr[i]; j<eptr[i+1]; j++)
      nind[nptr[eind[j]]++] = i;
  }
  SHIFTCSR(i, *nn, nptr);

  /* partition the other side of the mesh */
  InduceRowPartFromColumnPart(*nn, nptr, nind, npart, epart, *nparts, tpwgts);

  gk_free((void **)&nptr, &nind, LTERM);


SIGTHROW:
  if (renumber) {
    ChangeMesh2FNumbering2(*ne, *nn, eptr, eind, epart, npart);
    options[METIS_OPTION_NUMBERING] = 1;
  }

  METIS_Free(xadj);
  METIS_Free(adjncy);

  gk_siguntrap();
  gk_malloc_cleanup(0);

  return metis_rcode(sigrval);
}
Пример #26
0
/*************************************************************************
* 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);
  }