From: Denis Davydov <davydden@gmail.com>
Date: Fri, 12 May 2017 09:34:58 +0000 (+0200)
Subject: add another MF GMG test which was failing prior to cb5c93d
X-Git-Tag: v9.0.0-rc1~1604^2
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F4374%2Fhead;p=dealii.git

add another MF GMG test which was failing prior to cb5c93d
---

diff --git a/tests/matrix_free/parallel_multigrid_adaptive_05.cc b/tests/matrix_free/parallel_multigrid_adaptive_05.cc
new file mode 100644
index 0000000000..8355c969bc
--- /dev/null
+++ b/tests/matrix_free/parallel_multigrid_adaptive_05.cc
@@ -0,0 +1,581 @@
+// ---------------------------------------------------------------------
+//
+// Copyright (C) 2014 - 2017 by the deal.II authors
+//
+// This file is part of the deal.II library.
+//
+// The deal.II library is free software; you can use it, redistribute
+// it, and/or modify it under the terms of the GNU Lesser General
+// Public License as published by the Free Software Foundation; either
+// version 2.1 of the License, or (at your option) any later version.
+// The full text of the license can be found in the file LICENSE at
+// the top level of the deal.II distribution.
+//
+// ---------------------------------------------------------------------
+
+
+// same test as parallel_multigrid_adaptive_03 but using partition_color
+
+#include "../tests.h"
+
+#include <deal.II/base/logstream.h>
+#include <deal.II/base/utilities.h>
+#include <deal.II/lac/la_parallel_vector.h>
+#include <deal.II/lac/solver_cg.h>
+#include <deal.II/lac/precondition.h>
+#include <deal.II/grid/tria.h>
+#include <deal.II/grid/grid_generator.h>
+#include <deal.II/dofs/dof_handler.h>
+#include <deal.II/lac/constraint_matrix.h>
+#include <deal.II/fe/fe_q.h>
+#include <deal.II/fe/mapping_q.h>
+#include <deal.II/numerics/vector_tools.h>
+#include <deal.II/distributed/tria.h>
+
+#include <deal.II/multigrid/multigrid.h>
+#include <deal.II/multigrid/mg_transfer_matrix_free.h>
+#include <deal.II/multigrid/mg_tools.h>
+#include <deal.II/multigrid/mg_coarse.h>
+#include <deal.II/multigrid/mg_smoother.h>
+#include <deal.II/multigrid/mg_matrix.h>
+
+#include <deal.II/matrix_free/matrix_free.h>
+#include <deal.II/matrix_free/fe_evaluation.h>
+
+
+template <int dim, int fe_degree, int n_q_points_1d = fe_degree+1, typename number=double>
+class LaplaceOperator : public Subscriptor
+{
+public:
+  typedef number value_type;
+
+  LaplaceOperator() {};
+
+
+  void initialize (const Mapping<dim> &mapping,
+                   const DoFHandler<dim> &dof_handler,
+                   const MGConstrainedDoFs &mg_constrained_dofs,
+                   const typename FunctionMap<dim>::type &dirichlet_boundary,
+                   const unsigned int level,
+                   const bool threaded)
+  {
+    const QGauss<1> quad (n_q_points_1d);
+    typename MatrixFree<dim,number>::AdditionalData addit_data;
+    if (threaded)
+      addit_data.tasks_parallel_scheme = MatrixFree<dim,number>::AdditionalData::partition_color;
+    else
+      addit_data.tasks_parallel_scheme = MatrixFree<dim,number>::AdditionalData::none;
+    addit_data.tasks_block_size = 3;
+    addit_data.level_mg_handler = level;
+    ConstraintMatrix constraints;
+    if (level == numbers::invalid_unsigned_int)
+      {
+        IndexSet relevant_dofs;
+        DoFTools::extract_locally_relevant_dofs(dof_handler, relevant_dofs);
+        constraints.reinit(relevant_dofs);
+        DoFTools::make_hanging_node_constraints(dof_handler, constraints);
+        VectorTools::interpolate_boundary_values(dof_handler, dirichlet_boundary,
+                                                 constraints);
+      }
+    else
+      {
+        IndexSet relevant_dofs;
+        DoFTools::extract_locally_relevant_level_dofs(dof_handler, level,
+                                                      relevant_dofs);
+        constraints.reinit(relevant_dofs);
+        constraints.add_lines(mg_constrained_dofs.get_boundary_indices(level));
+
+        std::vector<types::global_dof_index> interface_indices;
+        mg_constrained_dofs.get_refinement_edge_indices(level).fill_index_vector(interface_indices);
+        edge_constrained_indices.clear();
+        edge_constrained_indices.reserve(interface_indices.size());
+        edge_constrained_values.resize(interface_indices.size());
+        const IndexSet &locally_owned = dof_handler.locally_owned_mg_dofs(level);
+        for (unsigned int i=0; i<interface_indices.size(); ++i)
+          if (locally_owned.is_element(interface_indices[i]))
+            edge_constrained_indices.push_back(locally_owned.index_within_set(interface_indices[i]));
+        have_interface_matrices = Utilities::MPI::max((unsigned int)edge_constrained_indices.size(), MPI_COMM_WORLD) > 0;
+      }
+    constraints.close();
+
+    data.reinit (mapping, dof_handler, constraints, quad, addit_data);
+
+    if (level != numbers::invalid_unsigned_int)
+      compute_inverse_diagonal();
+  }
+
+  void vmult(LinearAlgebra::distributed::Vector<number> &dst,
+             const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    dst = 0;
+    vmult_add(dst, src);
+  }
+
+  void Tvmult(LinearAlgebra::distributed::Vector<number> &dst,
+              const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    dst = 0;
+    vmult_add(dst, src);
+  }
+
+  void Tvmult_add(LinearAlgebra::distributed::Vector<number> &dst,
+                  const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    vmult_add(dst, src);
+  }
+
+  void vmult_add(LinearAlgebra::distributed::Vector<number> &dst,
+                 const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    Assert(src.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+    Assert(dst.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+
+    // set zero Dirichlet values on the input vector (and remember the src and
+    // dst values because we need to reset them at the end)
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        edge_constrained_values[i] =
+          std::pair<number,number>(src.local_element(edge_constrained_indices[i]),
+                                   dst.local_element(edge_constrained_indices[i]));
+        const_cast<LinearAlgebra::distributed::Vector<number>&>(src).local_element(edge_constrained_indices[i]) = 0.;
+      }
+
+    data.cell_loop (&LaplaceOperator::local_apply,
+                    this, dst, src);
+
+    const std::vector<unsigned int> &
+    constrained_dofs = data.get_constrained_dofs();
+    for (unsigned int i=0; i<constrained_dofs.size(); ++i)
+      dst.local_element(constrained_dofs[i]) += src.local_element(constrained_dofs[i]);
+
+    // reset edge constrained values, multiply by unit matrix and add into
+    // destination
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        const_cast<LinearAlgebra::distributed::Vector<number>&>(src).local_element(edge_constrained_indices[i]) = edge_constrained_values[i].first;
+        dst.local_element(edge_constrained_indices[i]) = edge_constrained_values[i].second + edge_constrained_values[i].first;
+      }
+  }
+
+  void vmult_interface_down(LinearAlgebra::distributed::Vector<number> &dst,
+                            const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    Assert(src.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+    Assert(dst.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+
+    dst = 0;
+
+    if (!have_interface_matrices)
+      return;
+
+    // set zero Dirichlet values on the input vector (and remember the src and
+    // dst values because we need to reset them at the end)
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        const double src_val = src.local_element(edge_constrained_indices[i]);
+        const_cast<LinearAlgebra::distributed::Vector<number>&>(src).local_element(edge_constrained_indices[i]) = 0.;
+        edge_constrained_values[i] = std::pair<number,number>(src_val,
+                                                              dst.local_element(edge_constrained_indices[i]));
+      }
+
+    data.cell_loop (&LaplaceOperator::local_apply,
+                    this, dst, src);
+
+    unsigned int c=0;
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        for ( ; c<edge_constrained_indices[i]; ++c)
+          dst.local_element(c) = 0.;
+        ++c;
+
+        // reset the src values
+        const_cast<LinearAlgebra::distributed::Vector<number>&>(src).local_element(edge_constrained_indices[i]) = edge_constrained_values[i].first;
+      }
+    for ( ; c<dst.local_size(); ++c)
+      dst.local_element(c) = 0.;
+  }
+
+  void vmult_interface_up(LinearAlgebra::distributed::Vector<number> &dst,
+                          const LinearAlgebra::distributed::Vector<number> &src) const
+  {
+    Assert(src.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+    Assert(dst.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner), ExcInternalError());
+
+    dst = 0;
+
+    if (!have_interface_matrices)
+      return;
+
+    LinearAlgebra::distributed::Vector<number> src_cpy (src);
+    unsigned int c=0;
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        for ( ; c<edge_constrained_indices[i]; ++c)
+          src_cpy.local_element(c) = 0.;
+        ++c;
+      }
+    for ( ; c<src_cpy.local_size(); ++c)
+      src_cpy.local_element(c) = 0.;
+
+    data.cell_loop (&LaplaceOperator::local_apply,
+                    this, dst, src_cpy);
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        dst.local_element(edge_constrained_indices[i]) = 0.;
+      }
+  }
+
+  types::global_dof_index m() const
+  {
+    return data.get_vector_partitioner()->size();
+  }
+
+  types::global_dof_index n() const
+  {
+    return data.get_vector_partitioner()->size();
+  }
+
+  number el (const unsigned int row,  const unsigned int col) const
+  {
+    AssertThrow(false, ExcMessage("Matrix-free does not allow for entry access"));
+    return number();
+  }
+
+  void
+  initialize_dof_vector(LinearAlgebra::distributed::Vector<number> &vector) const
+  {
+    if (!vector.partitioners_are_compatible(*data.get_dof_info(0).vector_partitioner))
+      data.initialize_dof_vector(vector);
+    Assert(vector.partitioners_are_globally_compatible(*data.get_dof_info(0).vector_partitioner),
+           ExcInternalError());
+  }
+
+  const LinearAlgebra::distributed::Vector<number> &
+  get_matrix_diagonal_inverse() const
+  {
+    Assert(inverse_diagonal_entries.size() > 0, ExcNotInitialized());
+    return inverse_diagonal_entries;
+  }
+
+
+private:
+  void
+  local_apply (const MatrixFree<dim,number>                &data,
+               LinearAlgebra::distributed::Vector<number>       &dst,
+               const LinearAlgebra::distributed::Vector<number> &src,
+               const std::pair<unsigned int,unsigned int>  &cell_range) const
+  {
+    FEEvaluation<dim,fe_degree,n_q_points_1d,1,number> phi (data);
+
+    for (unsigned int cell=cell_range.first; cell<cell_range.second; ++cell)
+      {
+        phi.reinit (cell);
+        phi.read_dof_values(src);
+        phi.evaluate (false,true,false);
+        for (unsigned int q=0; q<phi.n_q_points; ++q)
+          phi.submit_gradient (phi.get_gradient(q), q);
+        phi.integrate (false,true);
+        phi.distribute_local_to_global (dst);
+      }
+  }
+
+  void
+  compute_inverse_diagonal ()
+  {
+    data.initialize_dof_vector(inverse_diagonal_entries);
+    unsigned int dummy;
+    data.cell_loop (&LaplaceOperator::local_diagonal_cell,
+                    this, inverse_diagonal_entries, dummy);
+
+    const std::vector<unsigned int> &
+    constrained_dofs = data.get_constrained_dofs();
+    for (unsigned int i=0; i<constrained_dofs.size(); ++i)
+      inverse_diagonal_entries.local_element(constrained_dofs[i]) = 1.;
+    for (unsigned int i=0; i<edge_constrained_indices.size(); ++i)
+      {
+        inverse_diagonal_entries.local_element(edge_constrained_indices[i]) = 1.;
+      }
+
+
+    for (unsigned int i=0; i<inverse_diagonal_entries.local_size(); ++i)
+      if (std::abs(inverse_diagonal_entries.local_element(i)) > 1e-10)
+        inverse_diagonal_entries.local_element(i) = 1./inverse_diagonal_entries.local_element(i);
+      else
+        inverse_diagonal_entries.local_element(i) = 1.;
+  }
+
+  void
+  local_diagonal_cell (const MatrixFree<dim,number>                &data,
+                       LinearAlgebra::distributed::Vector<number>       &dst,
+                       const unsigned int &,
+                       const std::pair<unsigned int,unsigned int>  &cell_range) const
+  {
+    FEEvaluation<dim,fe_degree,n_q_points_1d,1,number> phi (data);
+
+    for (unsigned int cell=cell_range.first; cell<cell_range.second; ++cell)
+      {
+        phi.reinit (cell);
+
+        VectorizedArray<number> local_diagonal_vector[phi.tensor_dofs_per_cell];
+        for (unsigned int i=0; i<phi.dofs_per_cell; ++i)
+          {
+            for (unsigned int j=0; j<phi.dofs_per_cell; ++j)
+              phi.begin_dof_values()[j] = VectorizedArray<number>();
+            phi.begin_dof_values()[i] = 1.;
+            phi.evaluate (false,true,false);
+            for (unsigned int q=0; q<phi.n_q_points; ++q)
+              phi.submit_gradient (phi.get_gradient(q), q);
+            phi.integrate (false,true);
+            local_diagonal_vector[i] = phi.begin_dof_values()[i];
+          }
+        for (unsigned int i=0; i<phi.tensor_dofs_per_cell; ++i)
+          phi.begin_dof_values()[i] = local_diagonal_vector[i];
+        phi.distribute_local_to_global (dst);
+      }
+  }
+
+  MatrixFree<dim,number> data;
+  LinearAlgebra::distributed::Vector<number> inverse_diagonal_entries;
+  std::vector<unsigned int> edge_constrained_indices;
+  mutable std::vector<std::pair<number,number> > edge_constrained_values;
+  bool have_interface_matrices;
+};
+
+
+
+template <typename LAPLACEOPERATOR>
+class MGInterfaceMatrix : public Subscriptor
+{
+public:
+  void initialize (const LAPLACEOPERATOR &laplace)
+  {
+    this->laplace = &laplace;
+  }
+
+  void vmult (LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> &dst,
+              const LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> &src) const
+  {
+    laplace->vmult_interface_down(dst, src);
+  }
+
+  void Tvmult (LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> &dst,
+               const LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> &src) const
+  {
+    laplace->vmult_interface_up(dst, src);
+  }
+
+private:
+  SmartPointer<const LAPLACEOPERATOR> laplace;
+};
+
+
+
+template <int dim, typename LAPLACEOPERATOR>
+class MGTransferMF : public MGTransferMatrixFree<dim, typename LAPLACEOPERATOR::value_type>
+{
+public:
+  MGTransferMF(const MGLevelObject<LAPLACEOPERATOR> &laplace,
+               const MGConstrainedDoFs &mg_constrained_dofs)
+    :
+    MGTransferMatrixFree<dim, typename LAPLACEOPERATOR::value_type>(mg_constrained_dofs),
+    laplace_operator (laplace)
+  {
+  }
+
+  /**
+   * Overload copy_to_mg from MGTransferPrebuilt to get the vectors compatible
+   * with MatrixFree and bypass the crude vector initialization in
+   * MGTransferPrebuilt
+   */
+  template <class InVector, int spacedim>
+  void
+  copy_to_mg (const DoFHandler<dim,spacedim> &mg_dof_handler,
+              MGLevelObject<LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> > &dst,
+              const InVector &src) const
+  {
+    for (unsigned int level=dst.min_level();
+         level<=dst.max_level(); ++level)
+      laplace_operator[level].initialize_dof_vector(dst[level]);
+    MGLevelGlobalTransfer<LinearAlgebra::distributed::Vector<typename LAPLACEOPERATOR::value_type> >::
+    copy_to_mg(mg_dof_handler, dst, src);
+  }
+
+private:
+  const MGLevelObject<LAPLACEOPERATOR> &laplace_operator;
+};
+
+
+
+template<typename MatrixType, typename Number>
+class MGCoarseIterative : public MGCoarseGridBase<LinearAlgebra::distributed::Vector<Number> >
+{
+public:
+  MGCoarseIterative() {}
+
+  void initialize(const MatrixType &matrix)
+  {
+    coarse_matrix = &matrix;
+  }
+
+  virtual void operator() (const unsigned int   level,
+                           LinearAlgebra::distributed::Vector<Number> &dst,
+                           const LinearAlgebra::distributed::Vector<Number> &src) const
+  {
+    ReductionControl solver_control (1e4, 1e-50, 1e-10);
+    SolverCG<LinearAlgebra::distributed::Vector<Number> > solver_coarse (solver_control);
+    solver_coarse.solve (*coarse_matrix, dst, src, PreconditionIdentity());
+  }
+
+  const MatrixType *coarse_matrix;
+};
+
+
+
+
+template <int dim, int fe_degree, int n_q_points_1d, typename number>
+void do_test (const DoFHandler<dim>  &dof, const bool threaded)
+{
+  deallog << "Testing " << dof.get_fe().get_name();
+  deallog << std::endl;
+  deallog << "Number of degrees of freedom: " << dof.n_dofs() << std::endl;
+
+  ConstraintMatrix hanging_node_constraints;
+  IndexSet locally_relevant_dofs;
+  DoFTools::extract_locally_relevant_dofs(dof, locally_relevant_dofs);
+  hanging_node_constraints.reinit(locally_relevant_dofs);
+  DoFTools::make_hanging_node_constraints(dof, hanging_node_constraints);
+  hanging_node_constraints.close();
+
+  MGConstrainedDoFs mg_constrained_dofs;
+  ZeroFunction<dim> zero_function;
+  typename FunctionMap<dim>::type dirichlet_boundary;
+  dirichlet_boundary[0] = &zero_function;
+  mg_constrained_dofs.initialize(dof, dirichlet_boundary);
+
+  MappingQ<dim> mapping(fe_degree+1);
+  LaplaceOperator<dim,fe_degree,n_q_points_1d,double> fine_matrix;
+  fine_matrix.initialize(mapping, dof, mg_constrained_dofs, dirichlet_boundary,
+                         numbers::invalid_unsigned_int, threaded);
+
+  LinearAlgebra::distributed::Vector<double> in, sol;
+  fine_matrix.initialize_dof_vector(in);
+  fine_matrix.initialize_dof_vector(sol);
+
+  // set constant rhs vector
+  for (unsigned int i=0; i<in.local_size(); ++i)
+    if (!hanging_node_constraints.is_constrained(in.get_partitioner()->local_to_global(i)))
+      in.local_element(i) = 1.;
+
+  // set up multigrid in analogy to step-37
+  typedef LaplaceOperator<dim,fe_degree,n_q_points_1d,number> LevelMatrixType;
+
+  MGLevelObject<LevelMatrixType> mg_matrices;
+  mg_matrices.resize(0, dof.get_triangulation().n_global_levels()-1);
+  for (unsigned int level = 0; level<dof.get_triangulation().n_global_levels(); ++level)
+    {
+      mg_matrices[level].initialize(mapping, dof, mg_constrained_dofs,
+                                    dirichlet_boundary, level, threaded);
+    }
+  MGLevelObject<MGInterfaceMatrix<LevelMatrixType> > mg_interface_matrices;
+  mg_interface_matrices.resize(0, dof.get_triangulation().n_global_levels()-1);
+  for (unsigned int level=0; level<dof.get_triangulation().n_global_levels(); ++level)
+    mg_interface_matrices[level].initialize(mg_matrices[level]);
+
+  MGTransferMF<dim,LevelMatrixType> mg_transfer(mg_matrices,
+                                                mg_constrained_dofs);
+  mg_transfer.build(dof);
+
+  MGCoarseIterative<LevelMatrixType,number> mg_coarse;
+  mg_coarse.initialize(mg_matrices[0]);
+
+  typedef PreconditionChebyshev<LevelMatrixType,LinearAlgebra::distributed::Vector<number> > SMOOTHER;
+  MGSmootherPrecondition<LevelMatrixType, SMOOTHER, LinearAlgebra::distributed::Vector<number> >
+  mg_smoother;
+
+  MGLevelObject<typename SMOOTHER::AdditionalData> smoother_data;
+  smoother_data.resize(0, dof.get_triangulation().n_global_levels()-1);
+  for (unsigned int level = 0; level<dof.get_triangulation().n_global_levels(); ++level)
+    {
+      smoother_data[level].smoothing_range = 15.;
+      smoother_data[level].degree = 5;
+      smoother_data[level].eig_cg_n_iterations = 15;
+      smoother_data[level].preconditioner.
+      reset(new DiagonalMatrix<LinearAlgebra::distributed::Vector<number> >());
+      smoother_data[level].preconditioner->get_vector() =
+        mg_matrices[level].get_matrix_diagonal_inverse();
+    }
+
+  mg_smoother.initialize(mg_matrices, smoother_data);
+
+  mg::Matrix<LinearAlgebra::distributed::Vector<number> >
+  mg_matrix(mg_matrices);
+  mg::Matrix<LinearAlgebra::distributed::Vector<number> >
+  mg_interface(mg_interface_matrices);
+
+  Multigrid<LinearAlgebra::distributed::Vector<number> > mg(dof,
+                                                            mg_matrix,
+                                                            mg_coarse,
+                                                            mg_transfer,
+                                                            mg_smoother,
+                                                            mg_smoother);
+  mg.set_edge_matrices(mg_interface, mg_interface);
+  PreconditionMG<dim, LinearAlgebra::distributed::Vector<number>,
+                 MGTransferMF<dim,LevelMatrixType> >
+                 preconditioner(dof, mg, mg_transfer);
+
+  {
+    // avoid output from inner (coarse-level) solver
+    deallog.depth_file(3);
+
+    ReductionControl control(30, 1e-20, 1e-7);
+    SolverCG<LinearAlgebra::distributed::Vector<double> > solver(control);
+    solver.solve(fine_matrix, sol, in, preconditioner);
+  }
+}
+
+
+
+template <int dim, int fe_degree, typename Number>
+void test ()
+{
+  parallel::distributed::Triangulation<dim> tria(MPI_COMM_WORLD,
+                                                 Triangulation<dim>::limit_level_difference_at_vertices,
+                                                 parallel::distributed::Triangulation<dim>::construct_multigrid_hierarchy);
+  GridGenerator::hyper_cube (tria);
+  tria.refine_global(8-2*dim);
+  const unsigned int n_runs = fe_degree == 1 ? 6-dim : 5-dim;
+  for (unsigned int i=0; i<n_runs; ++i)
+    {
+      for (typename Triangulation<dim>::active_cell_iterator cell=tria.begin_active();
+           cell != tria.end(); ++cell)
+        if (cell->is_locally_owned() &&
+            ((cell->center().norm() < 0.5 && (cell->level() < 5 ||
+                                              cell->center().norm() > 0.45))
+             ||
+             (dim == 2 && cell->center().norm() > 1.2)))
+          cell->set_refine_flag();
+      tria.execute_coarsening_and_refinement();
+      FE_Q<dim> fe (fe_degree);
+      DoFHandler<dim> dof (tria);
+      dof.distribute_dofs(fe);
+      dof.distribute_mg_dofs(fe);
+
+      deallog.push("threaded");
+      do_test<dim, fe_degree, fe_degree+1, Number> (dof, true);
+      deallog.pop();
+    }
+}
+
+
+
+int main (int argc, char **argv)
+{
+  // The original issue with partition_color
+  // is hit with 2 threads and 4 cores.
+  Utilities::MPI::MPI_InitFinalize mpi_init(argc, argv, 2);
+
+  mpi_initlog();
+  deallog.threshold_double(1e-9);
+
+  test<2,1,double>();
+}
diff --git a/tests/matrix_free/parallel_multigrid_adaptive_05.with_mpi=true.with_p4est=true.mpirun=4.output b/tests/matrix_free/parallel_multigrid_adaptive_05.with_mpi=true.with_p4est=true.mpirun=4.output
new file mode 100644
index 0000000000..7916f86cb3
--- /dev/null
+++ b/tests/matrix_free/parallel_multigrid_adaptive_05.with_mpi=true.with_p4est=true.mpirun=4.output
@@ -0,0 +1,17 @@
+
+DEAL:threaded::Testing FE_Q<2>(1)
+DEAL:threaded::Number of degrees of freedom: 507
+DEAL:threaded:cg::Starting value 21.9317
+DEAL:threaded:cg::Convergence step 5 value 7.81205e-07
+DEAL:threaded::Testing FE_Q<2>(1)
+DEAL:threaded::Number of degrees of freedom: 881
+DEAL:threaded:cg::Starting value 27.7669
+DEAL:threaded:cg::Convergence step 6 value 9.24482e-07
+DEAL:threaded::Testing FE_Q<2>(1)
+DEAL:threaded::Number of degrees of freedom: 2147
+DEAL:threaded:cg::Starting value 43.2551
+DEAL:threaded:cg::Convergence step 6 value 1.14520e-06
+DEAL:threaded::Testing FE_Q<2>(1)
+DEAL:threaded::Number of degrees of freedom: 6517
+DEAL:threaded:cg::Starting value 76.9220
+DEAL:threaded:cg::Convergence step 6 value 1.55925e-06