parti_zoltan.hpp

// FEAT3: Finite Element Analysis Toolbox, Version 3
// Copyright (C) 2010 by Stefan Turek & the FEAT group
// FEAT3 is released under the GNU General Public License version 3,
// see the file 'copyright.txt' in the top level directory for details.
 
#pragma once
 
#include <kernel/base_header.hpp>
 
#if defined(FEAT_HAVE_ZOLTAN) || defined(DOXYGEN)
#include <kernel/util/dist.hpp>
#include <kernel/adjacency/graph.hpp>
#include <kernel/adjacency/coloring.hpp>
#include <kernel/geometry/conformal_mesh.hpp>
 
namespace FEAT
{
  namespace Geometry
  {
    class PartiZoltan
    {
    public:
      class Hypergraph
      {
      public:
        Index first_elem;
        Adjacency::Graph sub_graph;
        std::vector<float> weights;
 
        Hypergraph() :
          first_elem(0u),
          sub_graph(),
          weights()
        {
        }
      }; // class Hypergraph
 
    private:
      const Dist::Comm& _comm;
      Dist::Comm _zoltan_comm;
      int _max_procs;
      Index _min_elems;
      Index _num_elems;
      Index _num_parts;
      Hypergraph _hypergraph;
      Adjacency::Coloring _coloring;
      void* _zz;
 
    public:
      explicit PartiZoltan(const Dist::Comm& comm, Index min_elems = 1000u, int max_procs = 1000);
 
      virtual ~PartiZoltan();
 
      template<int n_>
      bool execute(const IndexSet<n_>& faces_at_elem, const Index num_parts, const std::vector<Real>& weights)
      {
        Adjacency::Graph graph(Adjacency::RenderType::as_is, faces_at_elem);
        return execute(graph, num_parts, weights);
      }
 
      bool execute(const Adjacency::Graph& faces_at_elem, const Index num_parts, const std::vector<Real>& weights);
 
      Adjacency::Graph build_elems_at_rank() const
      {
        return _coloring.create_partition_graph();
      }
 
      int get_sub_comm_size() const
      {
        return _zoltan_comm.size();
      }
 
    protected:
      void _create_hypergraph(const Adjacency::Graph& faces_at_elem, const std::vector<Real>& weights);
      bool _apply_zoltan();
      bool _gather_coloring(const int num_export, const int* export_parts);
      bool _broadcast_coloring(bool zoltan_ok);
    }; // class PartiZoltan
  } // namespace Geometry
} // namespace FEAT
 
#endif // FEAT_HAVE_ZOLTAN