Files
mfem/miniapps/performance/ex1p.cpp
T
Veselin Dobrev 667790ccf1 In the performance miniapps, add options to set the mesh refinements.
Run the miniapps/performance tests at coarser mesh resolutions, so that
the tests run faster.

Explicitly remove and ignore the temporary files created by the tests,
because, in some cases, they may not be removed automatically.
2017-09-30 20:25:17 -07:00

516 lines
17 KiB
C++

// MFEM Example 1 - Parallel High-Performance Version
//
// Compile with: make ex1p
//
// Sample runs: mpirun -np 4 ex1p -m ../../data/fichera.mesh -perf -mf -pc lor
// mpirun -np 4 ex1p -m ../../data/fichera.mesh -perf -asm -pc ho
// mpirun -np 4 ex1p -m ../../data/fichera.mesh -perf -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/fichera.mesh -std -asm -pc ho
// mpirun -np 4 ex1p -m ../../data/fichera.mesh -std -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/amr-hex.mesh -perf -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/amr-hex.mesh -std -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/ball-nurbs.mesh -perf -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/ball-nurbs.mesh -std -asm -pc ho -sc
// mpirun -np 4 ex1p -m ../../data/pipe-nurbs.mesh -perf -mf -pc lor
// mpirun -np 4 ex1p -m ../../data/pipe-nurbs.mesh -std -asm -pc ho -sc
//
// Description: This example code demonstrates the use of MFEM to define a
// simple finite element discretization of the Laplace problem
// -Delta u = 1 with homogeneous Dirichlet boundary conditions.
// Specifically, we discretize using a FE space of the specified
// order, or if order < 1 using an isoparametric/isogeometric
// space (i.e. quadratic for quadratic curvilinear mesh, NURBS for
// NURBS mesh, etc.)
//
// The example highlights the use of mesh refinement, finite
// element grid functions, as well as linear and bilinear forms
// corresponding to the left-hand side and right-hand side of the
// discrete linear system. We also cover the explicit elimination
// of essential boundary conditions, static condensation, and the
// optional connection to the GLVis tool for visualization.
#include "mfem-performance.hpp"
#include <fstream>
#include <iostream>
using namespace std;
using namespace mfem;
// Define template parameters for optimized build.
const Geometry::Type geom = Geometry::CUBE; // mesh elements (default: hex)
const int mesh_p = 3; // mesh curvature (default: 3)
const int sol_p = 3; // solution order (default: 3)
const int rdim = Geometry::Constants<geom>::Dimension;
const int ir_order = 2*sol_p+rdim-1;
// Static mesh type
typedef H1_FiniteElement<geom,mesh_p> mesh_fe_t;
typedef H1_FiniteElementSpace<mesh_fe_t> mesh_fes_t;
typedef TMesh<mesh_fes_t> mesh_t;
// Static solution finite element space type
typedef H1_FiniteElement<geom,sol_p> sol_fe_t;
typedef H1_FiniteElementSpace<sol_fe_t> sol_fes_t;
// Static quadrature, coefficient and integrator types
typedef TIntegrationRule<geom,ir_order> int_rule_t;
typedef TConstantCoefficient<> coeff_t;
typedef TIntegrator<coeff_t,TDiffusionKernel> integ_t;
// Static bilinear form type, combining the above types
typedef TBilinearForm<mesh_t,sol_fes_t,int_rule_t,integ_t> HPCBilinearForm;
int main(int argc, char *argv[])
{
// 1. Initialize MPI.
int num_procs, myid;
MPI_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &num_procs);
MPI_Comm_rank(MPI_COMM_WORLD, &myid);
// 2. Parse command-line options.
const char *mesh_file = "../../data/fichera.mesh";
int ser_ref_levels = -1;
int par_ref_levels = 1;
int order = sol_p;
const char *basis_type = "G"; // Gauss-Lobatto
bool static_cond = false;
const char *pc = "lor";
bool perf = true;
bool matrix_free = true;
bool visualization = 1;
OptionsParser args(argc, argv);
args.AddOption(&mesh_file, "-m", "--mesh",
"Mesh file to use.");
args.AddOption(&ser_ref_levels, "-rs", "--refine-serial",
"Number of times to refine the mesh uniformly in serial;"
" -1 = auto: <= 10,000 elements.");
args.AddOption(&par_ref_levels, "-rp", "--refine-parallel",
"Number of times to refine the mesh uniformly in parallel.");
args.AddOption(&order, "-o", "--order",
"Finite element order (polynomial degree) or -1 for"
" isoparametric space.");
args.AddOption(&basis_type, "-b", "--basis-type",
"Basis: G - Gauss-Lobatto, P - Positive, U - Uniform");
args.AddOption(&perf, "-perf", "--hpc-version", "-std", "--standard-version",
"Enable high-performance, tensor-based, assembly/evaluation.");
args.AddOption(&matrix_free, "-mf", "--matrix-free", "-asm", "--assembly",
"Use matrix-free evaluation or efficient matrix assembly in "
"the high-performance version.");
args.AddOption(&pc, "-pc", "--preconditioner",
"Preconditioner: lor - low-order-refined (matrix-free) AMG, "
"ho - high-order (assembled) AMG, none.");
args.AddOption(&static_cond, "-sc", "--static-condensation", "-no-sc",
"--no-static-condensation", "Enable static condensation.");
args.AddOption(&visualization, "-vis", "--visualization", "-no-vis",
"--no-visualization",
"Enable or disable GLVis visualization.");
args.Parse();
if (!args.Good())
{
if (myid == 0)
{
args.PrintUsage(cout);
}
MPI_Finalize();
return 1;
}
if (static_cond && perf && matrix_free)
{
if (myid == 0)
{
cout << "\nStatic condensation can not be used with matrix-free"
" evaluation!\n" << endl;
}
MPI_Finalize();
return 2;
}
MFEM_VERIFY(perf || !matrix_free,
"--standard-version is not compatible with --matrix-free");
if (myid == 0)
{
args.PrintOptions(cout);
}
enum PCType { NONE, LOR, HO };
PCType pc_choice;
if (!strcmp(pc, "ho")) { pc_choice = HO; }
else if (!strcmp(pc, "lor")) { pc_choice = LOR; }
else if (!strcmp(pc, "none")) { pc_choice = NONE; }
else
{
mfem_error("Invalid Preconditioner specified");
return 3;
}
// See class BasisType in fem/fe_coll.hpp for available basis types
int basis = BasisType::GetType(basis_type[0]);
if (myid == 0)
{
cout << "Using " << BasisType::Name(basis) << " basis ..." << endl;
}
// 3. Read the (serial) mesh from the given mesh file on all processors. We
// can handle triangular, quadrilateral, tetrahedral, hexahedral, surface
// and volume meshes with the same code.
Mesh *mesh = new Mesh(mesh_file, 1, 1);
int dim = mesh->Dimension();
// 4. Check if the optimized version matches the given mesh
if (perf)
{
if (myid == 0)
{
cout << "High-performance version using integration rule with "
<< int_rule_t::qpts << " points ..." << endl;
}
if (!mesh_t::MatchesGeometry(*mesh))
{
if (myid == 0)
{
cout << "The given mesh does not match the optimized 'geom' parameter.\n"
<< "Recompile with suitable 'geom' value." << endl;
}
delete mesh;
MPI_Finalize();
return 4;
}
else if (!mesh_t::MatchesNodes(*mesh))
{
if (myid == 0)
{
cout << "Switching the mesh curvature to match the "
<< "optimized value (order " << mesh_p << ") ..." << endl;
}
mesh->SetCurvature(mesh_p, false, -1, Ordering::byNODES);
}
}
// 5. Refine the serial mesh on all processors to increase the resolution. In
// this example we do 'ref_levels' of uniform refinement. We choose
// 'ref_levels' to be the largest number that gives a final mesh with no
// more than 10,000 elements, or as specified on the command line with the
// option '--refine-serial'.
{
int ref_levels = (ser_ref_levels != -1) ? ser_ref_levels :
(int)floor(log(10000./mesh->GetNE())/log(2.)/dim);
for (int l = 0; l < ref_levels; l++)
{
mesh->UniformRefinement();
}
}
if (!perf && mesh->NURBSext)
{
const int new_mesh_p = std::min(sol_p, mesh_p);
if (myid == 0)
{
cout << "NURBS mesh: switching the mesh curvature to be "
<< "min(sol_p, mesh_p) = " << new_mesh_p << " ..." << endl;
}
mesh->SetCurvature(new_mesh_p, false, -1, Ordering::byNODES);
}
// 6. Define a parallel mesh by a partitioning of the serial mesh. Refine
// this mesh further in parallel to increase the resolution. Once the
// parallel mesh is defined, the serial mesh can be deleted.
ParMesh *pmesh = new ParMesh(MPI_COMM_WORLD, *mesh);
delete mesh;
{
for (int l = 0; l < par_ref_levels; l++)
{
pmesh->UniformRefinement();
}
}
if (pmesh->MeshGenerator() & 1) // simplex mesh
{
MFEM_VERIFY(pc_choice != LOR, "triangle and tet meshes do not support"
" the LOR preconditioner yet");
}
// 7. Define a parallel finite element space on the parallel mesh. Here we
// use continuous Lagrange finite elements of the specified order. If
// order < 1, we instead use an isoparametric/isogeometric space.
FiniteElementCollection *fec;
if (order > 0)
{
fec = new H1_FECollection(order, dim, basis);
}
else if (pmesh->GetNodes())
{
fec = pmesh->GetNodes()->OwnFEC();
if (myid == 0)
{
cout << "Using isoparametric FEs: " << fec->Name() << endl;
}
}
else
{
fec = new H1_FECollection(order = 1, dim, basis);
}
ParFiniteElementSpace *fespace = new ParFiniteElementSpace(pmesh, fec);
HYPRE_Int size = fespace->GlobalTrueVSize();
if (myid == 0)
{
cout << "Number of finite element unknowns: " << size << endl;
}
ParMesh *pmesh_lor = NULL;
FiniteElementCollection *fec_lor = NULL;
ParFiniteElementSpace *fespace_lor = NULL;
if (pc_choice == LOR)
{
int basis_lor = basis;
if (basis == BasisType::Positive) { basis_lor=BasisType::ClosedUniform; }
pmesh_lor = new ParMesh(pmesh, order, basis_lor);
fec_lor = new H1_FECollection(1, dim);
fespace_lor = new ParFiniteElementSpace(pmesh_lor, fec_lor);
}
// 8. Check if the optimized version matches the given space
if (perf && !sol_fes_t::Matches(*fespace))
{
if (myid == 0)
{
cout << "The given order does not match the optimized parameter.\n"
<< "Recompile with suitable 'sol_p' value." << endl;
}
delete fespace;
delete fec;
delete mesh;
MPI_Finalize();
return 5;
}
// 9. Determine the list of true (i.e. parallel conforming) essential
// boundary dofs. In this example, the boundary conditions are defined
// by marking all the boundary attributes from the mesh as essential
// (Dirichlet) and converting them to a list of true dofs.
Array<int> ess_tdof_list;
if (pmesh->bdr_attributes.Size())
{
Array<int> ess_bdr(pmesh->bdr_attributes.Max());
ess_bdr = 1;
fespace->GetEssentialTrueDofs(ess_bdr, ess_tdof_list);
}
// 10. Set up the parallel linear form b(.) which corresponds to the
// right-hand side of the FEM linear system, which in this case is
// (1,phi_i) where phi_i are the basis functions in fespace.
ParLinearForm *b = new ParLinearForm(fespace);
ConstantCoefficient one(1.0);
b->AddDomainIntegrator(new DomainLFIntegrator(one));
b->Assemble();
// 11. Define the solution vector x as a parallel finite element grid
// function corresponding to fespace. Initialize x with initial guess of
// zero, which satisfies the boundary conditions.
ParGridFunction x(fespace);
x = 0.0;
// 12. Set up the parallel bilinear form a(.,.) on the finite element space
// that will hold the matrix corresponding to the Laplacian operator.
ParBilinearForm *a = new ParBilinearForm(fespace);
ParBilinearForm *a_pc = NULL;
if (pc_choice == LOR) { a_pc = new ParBilinearForm(fespace_lor); }
if (pc_choice == HO) { a_pc = new ParBilinearForm(fespace); }
// 13. Assemble the parallel bilinear form and the corresponding linear
// system, applying any necessary transformations such as: parallel
// assembly, eliminating boundary conditions, applying conforming
// constraints for non-conforming AMR, static condensation, etc.
if (static_cond)
{
a->EnableStaticCondensation();
MFEM_VERIFY(pc_choice != LOR,
"cannot use LOR preconditioner with static condensation");
}
if (myid == 0)
{
cout << "Assembling the matrix ..." << flush;
}
tic_toc.Clear();
tic_toc.Start();
// Pre-allocate sparsity assuming dense element matrices
a->UsePrecomputedSparsity();
HPCBilinearForm *a_hpc = NULL;
Operator *a_oper = NULL;
if (!perf)
{
// Standard assembly using a diffusion domain integrator
a->AddDomainIntegrator(new DiffusionIntegrator(one));
a->Assemble();
}
else
{
// High-performance assembly/evaluation using the templated operator type
a_hpc = new HPCBilinearForm(integ_t(coeff_t(1.0)), *fespace);
if (matrix_free)
{
a_hpc->Assemble(); // partial assembly
}
else
{
a_hpc->AssembleBilinearForm(*a); // full matrix assembly
}
}
tic_toc.Stop();
if (myid == 0)
{
cout << " done, " << tic_toc.RealTime() << "s." << endl;
}
// 14. Define and apply a parallel PCG solver for AX=B with the BoomerAMG
// preconditioner from hypre.
// Setup the operator matrix (if applicable)
HypreParMatrix A;
Vector B, X;
if (perf && matrix_free)
{
a_hpc->FormLinearSystem(ess_tdof_list, x, *b, a_oper, X, B);
HYPRE_Int glob_size = fespace->GlobalTrueVSize();
if (myid == 0)
{
cout << "Size of linear system: " << glob_size << endl;
}
}
else
{
a->FormLinearSystem(ess_tdof_list, x, *b, A, X, B);
HYPRE_Int glob_size = A.GetGlobalNumRows();
if (myid == 0)
{
cout << "Size of linear system: " << glob_size << endl;
}
a_oper = &A;
}
// Setup the matrix used for preconditioning
if (myid == 0)
{
cout << "Assembling the preconditioning matrix ..." << flush;
}
tic_toc.Clear();
tic_toc.Start();
HypreParMatrix A_pc;
if (pc_choice == LOR)
{
// TODO: assemble the LOR matrix using the performance code
a_pc->AddDomainIntegrator(new DiffusionIntegrator(one));
a_pc->UsePrecomputedSparsity();
a_pc->Assemble();
a_pc->FormSystemMatrix(ess_tdof_list, A_pc);
}
else if (pc_choice == HO)
{
if (!matrix_free)
{
A_pc.MakeRef(A); // matrix already assembled, reuse it
}
else
{
a_pc->UsePrecomputedSparsity();
a_hpc->AssembleBilinearForm(*a_pc);
a_pc->FormSystemMatrix(ess_tdof_list, A_pc);
}
}
tic_toc.Stop();
if (myid == 0)
{
cout << " done, " << tic_toc.RealTime() << "s." << endl;
}
// Solve with CG or PCG, depending if the matrix A_pc is available
CGSolver *pcg;
pcg = new CGSolver(MPI_COMM_WORLD);
pcg->SetRelTol(1e-6);
pcg->SetMaxIter(500);
pcg->SetPrintLevel(1);
HypreSolver *amg = NULL;
pcg->SetOperator(*a_oper);
if (pc_choice != NONE)
{
amg = new HypreBoomerAMG(A_pc);
pcg->SetPreconditioner(*amg);
}
tic_toc.Clear();
tic_toc.Start();
pcg->Mult(B, X);
tic_toc.Stop();
delete amg;
if (myid == 0)
{
// Note: In the pcg algorithm, the number of operator Mult() calls is
// N_iter and the number of preconditioner Mult() calls is N_iter+1.
cout << "Time per CG step: "
<< tic_toc.RealTime() / pcg->GetNumIterations() << "s." << endl;
}
// 15. Recover the parallel grid function corresponding to X. This is the
// local finite element solution on each processor.
if (perf && matrix_free)
{
a_hpc->RecoverFEMSolution(X, *b, x);
}
else
{
a->RecoverFEMSolution(X, *b, x);
}
// 16. Save the refined mesh and the solution in parallel. This output can
// be viewed later using GLVis: "glvis -np <np> -m mesh -g sol".
{
ostringstream mesh_name, sol_name;
mesh_name << "mesh." << setfill('0') << setw(6) << myid;
sol_name << "sol." << setfill('0') << setw(6) << myid;
ofstream mesh_ofs(mesh_name.str().c_str());
mesh_ofs.precision(8);
pmesh->Print(mesh_ofs);
ofstream sol_ofs(sol_name.str().c_str());
sol_ofs.precision(8);
x.Save(sol_ofs);
}
// 17. Send the solution by socket to a GLVis server.
if (visualization)
{
char vishost[] = "localhost";
int visport = 19916;
socketstream sol_sock(vishost, visport);
sol_sock << "parallel " << num_procs << " " << myid << "\n";
sol_sock.precision(8);
sol_sock << "solution\n" << *pmesh << x << flush;
}
// 18. Free the used memory.
delete a;
delete a_hpc;
if (a_oper != &A) { delete a_oper; }
delete a_pc;
delete b;
delete fespace;
delete fespace_lor;
delete fec_lor;
delete pmesh_lor;
if (order > 0) { delete fec; }
delete pmesh;
delete pcg;
MPI_Finalize();
return 0;
}