/// <summary>
/// Automatic choice of linear solver depending on problem size, immersed boundary, polynomial degree, etc.
/// </summary>
static ISolverSmootherTemplate AutomaticChoice(IBM_Control Control, XdgBDFTimestepping Timestepper)
{
//int pV = Control.FieldOptions["VelocityX"].Degree;
int pP = Control.FieldOptions["Pressure"].Degree;
int pV = pP + 1;
// Detecting variables for solver determination
var D = Timestepper.MultigridSequence[0].SpatialDimension;
var cellsLoc = Timestepper.MultigridSequence[0].CellPartitioning.LocalLength;
var cellsGlo = Timestepper.MultigridSequence[0].CellPartitioning.TotalLength;
ISolverSmootherTemplate tempsolve = null;
var size = Timestepper.MultigridSequence[0].CellPartitioning.MpiSize;
// !!!!!!!!!!!UNTERSCHEIDUNG OB PICARD ODER NEWTON!!!!!!!!!!!!
if (Timestepper.Config_NonlinearSolver == NonlinearSolverMethod.NewtonGMRES)
{
// Spatial Dimension
switch (D)
{
case 1:
break;
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
//break;
case 2:
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
//break;
case 3:
var dofsPerCell3D = (3 * (pV * pV * pV + 6 * pV * pV + 11 * pV + 6) / 6 + 1 * (pP * pP * pP + 6 * pP * pP + 11 * pP + 6) / 6);
var dofsLoc = dofsPerCell3D * cellsLoc;
var dofsGlo = dofsPerCell3D * cellsGlo;
var PPP = (int)Math.Ceiling(dofsLoc / 6500.0);
Console.WriteLine("Analysing the problem yields " + PPP + " parts per process.");
if (dofsGlo > 10000)
{
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
Timestepper.Config_linearSolver = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
NoOfPartsPerProcess = PPP,
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
};
}
else
{
Timestepper.Config_linearSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS
};
}
break;
default:
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
}
}
else
{
// Spatial Dimension
switch (D)
{
case 1:
break;
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
//break;
case 2:
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
//break;
case 3:
var dofsPerCell3D = (3 * (pV * pV * pV + 6 * pV * pV + 11 * pV + 6) / 6 + 1 * (pP * pP * pP + 6 * pP * pP + 11 * pP + 6) / 6);
var dofsLoc = dofsPerCell3D * cellsLoc;
var dofsGlo = dofsPerCell3D * cellsGlo;
if (dofsGlo > 10000)
{
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
tempsolve = new SoftGMRES()
{
MaxKrylovDim = Timestepper.Config_MaxKrylovDim,
m_Tolerance = Timestepper.Config_SolverConvergenceCriterion,
Precond = new Schwarz()
{
m_BlockingStrategy = new Schwarz.SimpleBlocking()
{
NoOfPartsPerProcess = (int)Math.Ceiling(dofsLoc / 6500.0),
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
},
};
}
else
{
tempsolve = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS
};
}
break;
default:
throw new NotImplementedException("Currently not implemented for " + D + " Dimensions");
}
}
return(tempsolve);
//Timestepper.
// Wenn Gesamtproblem in 2D < 100000 DoFs -> Direct Solver
// Wenn Gesamtproblem in 3D < 10000 DoFs -> Direct Solver
// Block Solve 3D ca. 6000 DoFs per Process -> Adjust Blocks per Process
// Coarse Solve ca. 5000 bis 10000 DoFs. -> Adjust Multigrid Levels
}
/// <summary>
/// Choose solver depending on configurations made in the control file.
/// </summary>
/// <param name="nonlinSol"></param>
/// <param name="linSol"></param>
/// <param name="Timestepper"></param>
public static void ChooseSolver(IBM_Control Control, ref XdgBDFTimestepping Timestepper)
{
// Set several solver options for Timestepper
Timestepper.Config_SolverConvergenceCriterion = Control.Solver_ConvergenceCriterion;
Timestepper.Config_MaxIterations = Control.MaxSolverIterations;
Timestepper.Config_MinIterations = Control.MinSolverIterations;
Timestepper.Config_MaxKrylovDim = Control.MaxKrylovDim;
// Set to pseudo Picard if the Stokes equations should be solved
if (Control.PhysicalParameters.IncludeConvection == false)
{
Control.NonlinearSolve = NonlinearSolverCodes.Picard;
}
ISolverSmootherTemplate templinearSolve = null;
switch (Control.LinearSolve)
{
case LinearSolverCodes.automatic:
templinearSolve = AutomaticChoice(Control, Timestepper);
break;
case LinearSolverCodes.classic_mumps:
templinearSolve = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS
};
break;
case LinearSolverCodes.classic_pardiso:
templinearSolve = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.PARDISO
};
break;
case LinearSolverCodes.exp_schwarz_directcoarse_overlap:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
NoOfPartsPerProcess = 1,
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
};
break;
case LinearSolverCodes.exp_schwarz_directcoarse:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
NoOfPartsPerProcess = 1,
},
Overlap = 0,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
};
break;
case LinearSolverCodes.exp_schwarz_Kcycle_directcoarse:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.MultigridBlocks()
{
Depth = Control.NoOfMultigridLevels - 1
},
Overlap = 0,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
};
break;
case LinearSolverCodes.exp_schwarz_Kcycle_directcoarse_overlap:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.MultigridBlocks()
{
Depth = Control.NoOfMultigridLevels - 1
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
};
break;
case LinearSolverCodes.exp_softgmres:
templinearSolve = new SoftGMRES()
{
MaxKrylovDim = Timestepper.Config_MaxKrylovDim,
m_Tolerance = Timestepper.Config_SolverConvergenceCriterion,
};
break;
case LinearSolverCodes.exp_softgmres_schwarz_Kcycle_directcoarse_overlap:
templinearSolve = new SoftGMRES()
{
MaxKrylovDim = Timestepper.Config_MaxKrylovDim,
m_Tolerance = Timestepper.Config_SolverConvergenceCriterion,
Precond = new Schwarz()
{
m_BlockingStrategy = new Schwarz.MultigridBlocks()
{
Depth = Control.NoOfMultigridLevels - 1
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
},
};
break;
case LinearSolverCodes.exp_softgmres_schwarz_directcoarse_overlap:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new SoftGMRES()
{
MaxKrylovDim = Timestepper.Config_MaxKrylovDim,
m_Tolerance = Timestepper.Config_SolverConvergenceCriterion,
Precond = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
NoOfPartsPerProcess = 1,
},
Overlap = 1,
CoarseSolver = DetermineMGSquence(Control.NoOfMultigridLevels - 2)
},
};
break;
case LinearSolverCodes.exp_multigrid:
if (Control.NoOfMultigridLevels < 2)
{
throw new ApplicationException("At least 2 Multigridlevels are required");
}
templinearSolve = new ILU()
{
};
break;
case LinearSolverCodes.exp_ILU:
templinearSolve = new ILU()
{
};
break;
case LinearSolverCodes.exp_Schur:
templinearSolve = new SchurPrecond()
{
SchurOpt = SchurPrecond.SchurOptions.decoupledApprox
};
break;
case LinearSolverCodes.exp_Simple:
templinearSolve = new SchurPrecond()
{
SchurOpt = SchurPrecond.SchurOptions.SIMPLE
};
break;
case LinearSolverCodes.exp_AS_1000:
if (Timestepper.MultigridSequence[0].SpatialDimension == 3) //3D --> 212940DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 76,
NoOfPartsPerProcess = 213, // Warum 76
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
else //2D --> 75088DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 213,
NoOfPartsPerProcess = 213,
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
break;
case LinearSolverCodes.exp_AS_5000:
if (Timestepper.MultigridSequence[0].SpatialDimension == 3) //3D --> 212940DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 43,
NoOfPartsPerProcess = 43,
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
else //2D --> 75088DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 16,
NoOfPartsPerProcess = 43,
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
break;
case LinearSolverCodes.exp_AS_10000:
if (Timestepper.MultigridSequence[0].SpatialDimension == 3) //3D --> 212940DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 22,
NoOfPartsPerProcess = 22,
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
else //2D --> 75088DoF
{
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.METISBlockingStrategy()
{
//noofparts = 8,
NoOfPartsPerProcess = 22, //
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
}
break;
case LinearSolverCodes.exp_AS_MG:
templinearSolve = new Schwarz()
{
m_BlockingStrategy = new Schwarz.MultigridBlocks()
{
//depth = asdepth,
Depth = 2,
},
CoarseSolver = new DirectSolver()
{
WhichSolver = DirectSolver._whichSolver.MUMPS //PARDISO
},
Overlap = 1
};
break;
case LinearSolverCodes.exp_localPrec:
templinearSolve = new LocalizedOperatorPrec()
{
m_dt = Control.GetFixedTimestep(),
m_muA = Control.PhysicalParameters.mu_A,
};
break;
default:
throw new NotImplementedException("Linear solver option not available");
}
// Set nonlinear Solver
switch (Control.NonlinearSolve)
{
case NonlinearSolverCodes.NewtonGMRES:
Timestepper.Config_NonlinearSolver = NonlinearSolverMethod.NewtonGMRES;
Timestepper.Config_linearSolver = templinearSolve;
break;
case NonlinearSolverCodes.Picard:
Timestepper.Config_NonlinearSolver = NonlinearSolverMethod.Picard;
Timestepper.Config_linearSolver = templinearSolve;
break;
case NonlinearSolverCodes.Newton:
Timestepper.Config_NonlinearSolver = NonlinearSolverMethod.Newton;
Timestepper.Config_linearSolver = templinearSolve;
break;
case NonlinearSolverCodes.PicardGMRES:
Timestepper.Config_NonlinearSolver = NonlinearSolverMethod.Picard;
Timestepper.Config_linearSolver = new SoftGMRES()
{
MaxKrylovDim = Timestepper.Config_MaxKrylovDim,
m_Tolerance = Timestepper.Config_SolverConvergenceCriterion,
Precond = templinearSolve,
m_MaxIterations = Timestepper.Config_MaxIterations,
};
break;
default:
throw new NotImplementedException("Nonlinear solver option not available");
}
}
