WIP: Add legacy flag for executing timestep execute in fixed point iteration

framework/include/executioners/Executioner.h

@@ -163,6 +163,9 @@ class Executioner : public MooseObject,
   virtual PostprocessorValue & addAttributeReporter(const std::string & name,
                                                     Real initial_value = 0);
 
+  /// Flag to indicate timestep_begin/end objects are to be executed within a fixed point iteration
+  const bool _legacy_execute_on;
+
   FEProblemBase & _fe_problem;
 
   MooseEnum _iteration_method;

framework/include/executioners/FixedPointSolve.h

@@ -23,6 +23,10 @@ class FixedPointSolve : public SolveObject
 
   static InputParameters validParams();
 
+  /// Custom execute flags for fixed point iterations
+  static const ExecFlagType EXEC_FIXEDPOINT_BEGIN;
+  static const ExecFlagType EXEC_FIXEDPOINT_END;
+
   /**
    * Iteratively solves the FEProblem.
    * @return True if solver is converged.
@@ -143,8 +147,8 @@ class FixedPointSolve : public SolveObject
   /**
    * Perform one fixed point iteration or a full solve.
    *
-   * @param begin_norm       Residual norm after timestep_begin execution
-   * @param end_norm         Residual norm after timestep_end execution
+   * @param begin_norm       Residual norm after fixedpoint_begin execution
+   * @param end_norm         Residual norm after fixedpoint_end execution
    * @param transformed_dofs DoFs targetted by the fixed point algorithm
    *
    * @return True if both nonlinear solve and the execution of multiapps are successful.
@@ -193,6 +197,8 @@ class FixedPointSolve : public SolveObject
   /// Print information about the fixed point convergence
   void printFixedPointConvergenceReason();
 
+  /// Flag to indicate timestep_begin/end objects are to be executed within a fixed point iteration
+  const bool _legacy_execute_on;
   /// Minimum fixed point iterations
   unsigned int _min_fixed_point_its;
   /// Maximum fixed point iterations
@@ -239,10 +245,10 @@ class FixedPointSolve : public SolveObject
   unsigned int _main_fixed_point_it;
   /// Initial residual norm
   Real _fixed_point_initial_norm;
-  /// Full history of residual norm after evaluation of timestep_begin
-  std::vector<Real> _fixed_point_timestep_begin_norm;
-  /// Full history of residual norm after evaluation of timestep_end
-  std::vector<Real> _fixed_point_timestep_end_norm;
+  /// Full history of residual norm after evaluation of fixedpoint_begin
+  std::vector<Real> _fixed_point_begin_norm;
+  /// Full history of residual norm after evaluation of fixedpoint_end
+  std::vector<Real> _fixed_point_end_norm;
   /// Status of fixed point solve
   MooseFixedPointConvergenceReason _fixed_point_status;
   ///@}

framework/src/base/MooseApp.C

@@ -358,6 +358,11 @@ MooseApp::validParams()
       "solution modifying objects are executed prior to the initial (0th nonlinear iteration) "
       "residual evaluation. The new behavior skips that redundant residual evaluation unless the "
       "parameter Executioner/use_pre_SMO_residual is set to true.");
+  params.addParam<bool>(
+      "use_legacy_fixed_point_execute_on",
+      true,
+      "The legacy behavior executes objects including aux kernels, user objects, postprocessors, "
+      "MultiApps, transfers, etc. on timestep_begin and timestep_end within a fixed point iteration.");
 
   params.addParam<bool>(
       MeshGeneratorSystem::allow_data_driven_param,

framework/src/executioners/Eigenvalue.C

@@ -257,6 +257,14 @@ Eigenvalue::execute()
 #endif // LIBMESH_ENABLE_AMR
     _eigen_problem.timestepSetup();
 
+    if (!_legacy_execute_on)
+    {
+      _eigen_problem.execute(EXEC_TIMESTEP_BEGIN);
+      _time = _time_step;
+      _eigen_problem.outputStep(EXEC_TIMESTEP_BEGIN);
+      _time = _system_time;
+    }
+
     _last_solve_converged = _fixed_point_solve->solve();
     if (!lastSolveConverged())
     {
@@ -270,6 +278,12 @@ Eigenvalue::execute()
       _eigen_problem.computeIndicators();
       _eigen_problem.computeMarkers();
     }
+
+    if (!_legacy_execute_on)
+    {
+      _eigen_problem.onTimestepEnd();
+      _eigen_problem.execute(EXEC_TIMESTEP_END);
+    }
     // need to keep _time in sync with _time_step to get correct output
     _time = _time_step;
     _eigen_problem.outputStep(EXEC_TIMESTEP_END);

framework/src/executioners/Executioner.C

@@ -58,6 +58,7 @@ Executioner::Executioner(const InputParameters & parameters)
     PostprocessorInterface(this),
     Restartable(this, "Executioners"),
     PerfGraphInterface(this),
+    _legacy_execute_on(_app.parameters().get<bool>("use_legacy_fixed_point_execute_on")),
     _fe_problem(*getCheckedPointerParam<FEProblemBase *>(
         "_fe_problem_base", "This might happen if you don't have a mesh")),
     _iteration_method(getParam<MooseEnum>("fixed_point_algorithm")),
@@ -91,6 +92,7 @@ Executioner::Executioner(const InputParameters & parameters, bool)
     PostprocessorInterface(this),
     Restartable(this, "Executioners"),
     PerfGraphInterface(this),
+    _legacy_execute_on(_app.parameters().get<bool>("use_legacy_fixed_point_execute_on")),
     _fe_problem(*getCheckedPointerParam<FEProblemBase *>(
         "_fe_problem_base", "This might happen if you don't have a mesh")),
     _iteration_method(getParam<MooseEnum>("fixed_point_algorithm")),

framework/src/executioners/FixedPointSolve.C

@@ -16,6 +16,10 @@
 #include "AllLocalDofIndicesThread.h"
 #include "Console.h"
 #include "EigenExecutionerBase.h"
+#include "ExecFlagRegistry.h"
+
+const ExecFlagType FixedPointSolve::EXEC_FIXEDPOINT_BEGIN = registerDefaultExecFlag("FIXEDPOINT_BEGIN");
+const ExecFlagType FixedPointSolve::EXEC_FIXEDPOINT_END = registerDefaultExecFlag("FIXEDPOINT_END");
 
 InputParameters
 FixedPointSolve::validParams()
@@ -51,7 +55,7 @@ FixedPointSolve::validParams()
   params.addParam<bool>(
       "fixed_point_force_norms",
       false,
-      "Force the evaluation of both the TIMESTEP_BEGIN and TIMESTEP_END norms regardless of the "
+      "Force the evaluation of residual norms after executing objects and MultiApps on fixedpoint_begin and fixedpoint_end regardless of the "
       "existence of active MultiApps with those execute_on flags, default: false.");
 
   // Parameters for using a custom postprocessor for convergence checks
@@ -116,7 +120,7 @@ FixedPointSolve::validParams()
       "Maximum number of times to update XFEM crack topology in a step due to evolving cracks");
   params.addParam<bool>("update_xfem_at_timestep_begin",
                         false,
-                        "Should XFEM update the mesh at the beginning of the timestep");
+                        "Should XFEM update the mesh at the beginning of a fixed point iteration");
 
   params.addParamNamesToGroup("max_xfem_update update_xfem_at_timestep_begin",
                               "XFEM fixed point iterations");
@@ -126,6 +130,7 @@ FixedPointSolve::validParams()
 
 FixedPointSolve::FixedPointSolve(Executioner & ex)
   : SolveObject(ex),
+    _legacy_execute_on(_app.parameters().get<bool>("use_legacy_fixed_point_execute_on")),
     _min_fixed_point_its(getParam<unsigned int>("fixed_point_min_its")),
     _max_fixed_point_its(getParam<unsigned int>("fixed_point_max_its")),
     _has_fixed_point_its(_max_fixed_point_its > 1),
@@ -198,18 +203,23 @@ FixedPointSolve::solve()
 
   Real current_dt = _problem.dt();
 
-  _fixed_point_timestep_begin_norm.clear();
-  _fixed_point_timestep_end_norm.clear();
-  _fixed_point_timestep_begin_norm.resize(_max_fixed_point_its);
-  _fixed_point_timestep_end_norm.resize(_max_fixed_point_its);
+  _fixed_point_begin_norm.clear();
+  _fixed_point_end_norm.clear();
+  _fixed_point_begin_norm.resize(_max_fixed_point_its);
+  _fixed_point_end_norm.resize(_max_fixed_point_its);
 
   bool converged = true;
 
   // need to back up multi-apps even when not doing fixed point iteration for recovering from failed
   // multiapp solve
   _problem.backupMultiApps(EXEC_MULTIAPP_FIXED_POINT_BEGIN);
-  _problem.backupMultiApps(EXEC_TIMESTEP_BEGIN);
-  _problem.backupMultiApps(EXEC_TIMESTEP_END);
+  if (_legacy_execute_on)
+  {
+    _problem.backupMultiApps(EXEC_TIMESTEP_BEGIN);
+    _problem.backupMultiApps(EXEC_TIMESTEP_END);
+  }
+  _problem.backupMultiApps(EXEC_FIXEDPOINT_BEGIN);
+  _problem.backupMultiApps(EXEC_FIXEDPOINT_END);
   _problem.backupMultiApps(EXEC_MULTIAPP_FIXED_POINT_END);
 
   // Prepare to relax variables as a main app
@@ -273,8 +283,13 @@ FixedPointSolve::solve()
       {
         // For every iteration other than the first, we need to restore the state of the MultiApps
         _problem.restoreMultiApps(EXEC_MULTIAPP_FIXED_POINT_BEGIN);
-        _problem.restoreMultiApps(EXEC_TIMESTEP_BEGIN);
-        _problem.restoreMultiApps(EXEC_TIMESTEP_END);
+        if (_legacy_execute_on)
+        {
+          _problem.restoreMultiApps(EXEC_TIMESTEP_BEGIN);
+          _problem.restoreMultiApps(EXEC_TIMESTEP_END);
+        }
+        _problem.restoreMultiApps(EXEC_FIXEDPOINT_BEGIN);
+        _problem.restoreMultiApps(EXEC_FIXEDPOINT_END);
         _problem.restoreMultiApps(EXEC_MULTIAPP_FIXED_POINT_END);
       }
 
@@ -288,8 +303,8 @@ FixedPointSolve::solve()
       _pp_old = *_fixed_point_custom_pp;
 
     // Solve a single application for one time step
-    bool solve_converged = solveStep(_fixed_point_timestep_begin_norm[_fixed_point_it],
-                                     _fixed_point_timestep_end_norm[_fixed_point_it],
+    bool solve_converged = solveStep(_fixed_point_begin_norm[_fixed_point_it],
+                                     _fixed_point_end_norm[_fixed_point_it],
                                      transformed_dofs);
 
     // Get new value and print history for the custom postprocessor convergence criterion
@@ -335,8 +350,8 @@ FixedPointSolve::solve()
         current_dt; // _dt might be smaller than this at this point for multistep methods
   }
 
-  // Save postprocessors after the solve and their potential timestep_end execution
-  // The postprocessors could be overwritten at timestep_begin, which is why they are saved
+  // Save postprocessors after the solve and their potential fixedpoint_end execution
+  // The postprocessors could be overwritten at fixedpoint_begin, which is why they are saved
   // after the solve. They could also be saved right after the transfers.
   if (_old_entering_time == _problem.time())
     savePostprocessorValues(false);
@@ -377,13 +392,15 @@ FixedPointSolve::solveStep(Real & begin_norm,
   bool auto_advance = autoAdvance();
 
   // Compute previous norms for coloring the norm output
-  Real begin_norm_old = (_fixed_point_it > 0 ? _fixed_point_timestep_begin_norm[_fixed_point_it - 1]
+  Real begin_norm_old = (_fixed_point_it > 0 ? _fixed_point_begin_norm[_fixed_point_it - 1]
                                              : std::numeric_limits<Real>::max());
-  Real end_norm_old = (_fixed_point_it > 0 ? _fixed_point_timestep_end_norm[_fixed_point_it - 1]
+  Real end_norm_old = (_fixed_point_it > 0 ? _fixed_point_end_norm[_fixed_point_it - 1]
                                            : std::numeric_limits<Real>::max());
 
   _executioner.preSolve();
-  _problem.execTransfers(EXEC_TIMESTEP_BEGIN);
+  if (_legacy_execute_on)
+    _problem.execTransfers(EXEC_TIMESTEP_BEGIN);
+  _problem.execTransfers(EXEC_FIXEDPOINT_BEGIN);
 
   if (_fixed_point_it == 0)
   {
@@ -397,7 +414,12 @@ FixedPointSolve::solveStep(Real & begin_norm,
     _problem.outputStep(EXEC_MULTIAPP_FIXED_POINT_BEGIN);
   }
 
-  if (!_problem.execMultiApps(EXEC_TIMESTEP_BEGIN, auto_advance))
+  if (_legacy_execute_on && !_problem.execMultiApps(EXEC_TIMESTEP_BEGIN, auto_advance))
+  {
+    _fixed_point_status = MooseFixedPointConvergenceReason::DIVERGED_FAILED_MULTIAPP;
+    return false;
+  }
+  if (!_problem.execMultiApps(EXEC_FIXEDPOINT_BEGIN, auto_advance))
   {
     _fixed_point_status = MooseFixedPointConvergenceReason::DIVERGED_FAILED_MULTIAPP;
     return false;
@@ -406,9 +428,11 @@ FixedPointSolve::solveStep(Real & begin_norm,
   if (_problem.haveXFEM() && _update_xfem_at_timestep_begin)
     _problem.updateMeshXFEM();
 
-  _problem.execute(EXEC_TIMESTEP_BEGIN);
+  if (_legacy_execute_on)
+    _problem.execute(EXEC_TIMESTEP_BEGIN);
+  _problem.execute(EXEC_FIXEDPOINT_BEGIN);
 
-  // Transform the fixed point postprocessors before solving, but after the timestep_begin transfers
+  // Transform the fixed point postprocessors before solving, but after the fixedpoint_begin transfers
   // have been received
   if (_transformed_pps.size() > 0 && useFixedPointAlgorithmUpdateInsteadOfPicard(true))
     transformPostprocessors(true);
@@ -417,16 +441,19 @@ FixedPointSolve::solveStep(Real & begin_norm,
     transformPostprocessors(false);
 
   if (_has_fixed_point_its && _has_fixed_point_norm)
-    if (_problem.hasMultiApps(EXEC_TIMESTEP_BEGIN) || _fixed_point_force_norms)
+    if ((_legacy_execute_on && _problem.hasMultiApps(EXEC_TIMESTEP_BEGIN)) ||
+        _problem.hasMultiApps(EXEC_FIXEDPOINT_BEGIN) || _fixed_point_force_norms)
     {
       begin_norm = _problem.computeResidualL2Norm();
 
-      _console << COLOR_MAGENTA << "Fixed point residual norm after TIMESTEP_BEGIN MultiApps: "
+      _console << COLOR_MAGENTA << "Fixed point residual norm after FIXEDPOINT_BEGIN MultiApps: "
                << Console::outputNorm(begin_norm_old, begin_norm) << std::endl;
     }
 
   // Perform output for timestep begin
-  _problem.outputStep(EXEC_TIMESTEP_BEGIN);
+  if (_legacy_execute_on)
+    _problem.outputStep(EXEC_TIMESTEP_BEGIN);
+  _problem.outputStep(EXEC_FIXEDPOINT_BEGIN);
 
   // Update warehouse active objects
   _problem.updateActiveObjects();
@@ -466,11 +493,22 @@ FixedPointSolve::solveStep(Real & begin_norm,
       _console << "\nXFEM did not modify mesh, continuing" << std::endl;
     }
 
-    _problem.onTimestepEnd();
-    _problem.execute(EXEC_TIMESTEP_END);
+    if (_legacy_execute_on)
+    {
+      _problem.onTimestepEnd();
+      _problem.execute(EXEC_TIMESTEP_END);
+
+      _problem.execTransfers(EXEC_TIMESTEP_END);
+      if (!_problem.execMultiApps(EXEC_TIMESTEP_END, auto_advance))
+      {
+        _fixed_point_status = MooseFixedPointConvergenceReason::DIVERGED_FAILED_MULTIAPP;
+        return false;
+      }
+    }
+    _problem.execute(EXEC_FIXEDPOINT_END);
 
-    _problem.execTransfers(EXEC_TIMESTEP_END);
-    if (!_problem.execMultiApps(EXEC_TIMESTEP_END, auto_advance))
+    _problem.execTransfers(EXEC_FIXEDPOINT_END);
+    if (!_problem.execMultiApps(EXEC_FIXEDPOINT_END, auto_advance))
     {
       _fixed_point_status = MooseFixedPointConvergenceReason::DIVERGED_FAILED_MULTIAPP;
       return false;
@@ -486,11 +524,12 @@ FixedPointSolve::solveStep(Real & begin_norm,
   _executioner.postSolve();
 
   if (_has_fixed_point_its && _has_fixed_point_norm)
-    if (_problem.hasMultiApps(EXEC_TIMESTEP_END) || _fixed_point_force_norms)
+    if ((_legacy_execute_on && _problem.hasMultiApps(EXEC_TIMESTEP_END)) ||
+        _problem.hasMultiApps(EXEC_FIXEDPOINT_END) || _fixed_point_force_norms)
     {
       end_norm = _problem.computeResidualL2Norm();
 
-      _console << COLOR_MAGENTA << "Fixed point residual norm after TIMESTEP_END MultiApps: "
+      _console << COLOR_MAGENTA << "Fixed point residual norm after FIXEDPOINT_END MultiApps: "
                << Console::outputNorm(end_norm_old, end_norm) << std::endl;
     }
 
@@ -516,8 +555,8 @@ FixedPointSolve::examineFixedPointConvergence(bool & converged)
 {
   if (_fixed_point_it + 2 > _min_fixed_point_its)
   {
-    Real max_norm = std::max(_fixed_point_timestep_begin_norm[_fixed_point_it],
-                             _fixed_point_timestep_end_norm[_fixed_point_it]);
+    Real max_norm = std::max(_fixed_point_begin_norm[_fixed_point_it],
+                             _fixed_point_end_norm[_fixed_point_it]);
 
     Real max_relative_drop = max_norm / _fixed_point_initial_norm;
 

framework/src/executioners/PicardSolve.C

@@ -24,8 +24,8 @@ PicardSolve::validParams()
       "picard_max_its",
       1,
       "Specifies the maximum number of Picard iterations. "
-      "Mainly used when  wanting to do Picard iterations with MultiApps "
-      "that are set to execute_on timestep_end or timestep_begin. "
+      "Mainly used when wanting to do Picard iterations with MultiApps "
+      "that are set to execute_on fixedpoint_end or fixedpoint_begin. "
       "Setting this parameter to 1 turns off the Picard iterations.",
       "Deprecated, use fixed_point_max_its");
   params.addDeprecatedParam<bool>(
@@ -60,7 +60,7 @@ PicardSolve::validParams()
   params.addDeprecatedParam<bool>(
       "picard_force_norms",
       false,
-      "Force the evaluation of both the TIMESTEP_BEGIN and TIMESTEP_END norms regardless of the "
+      "Force the evaluation of both the FIXEDPOINT_BEGIN and FIXEDPOINT_END norms regardless of the "
       "existence of active MultiApps with those execute_on flags, default: false.",
       "Deprecated, use fixed_point_force_norms");
 
@@ -266,7 +266,7 @@ PicardSolve::printFixedPointConvergenceHistory()
   for (unsigned int i = 0; i <= _fixed_point_it; ++i)
   {
     Real max_norm =
-        std::max(_fixed_point_timestep_begin_norm[i], _fixed_point_timestep_end_norm[i]);
+        std::max(_fixed_point_begin_norm[i], _fixed_point_end_norm[i]);
     _console << std::setw(2) << i + 1
              << " Picard |R| = " << Console::outputNorm(max_norm_old, max_norm) << '\n';
     max_norm_old = max_norm;

framework/src/executioners/SecantSolve.C

@@ -135,10 +135,10 @@ SecantSolve::savePostprocessorValues(const bool primary)
     (*transformed_pps_values)[i][2] = (*transformed_pps_values)[i][0];
 
     // Save current value
-    // Primary: this is done before the timestep's solves and before timestep_begin transfers,
+    // Primary: this is done before the fixedpoint's solves and before fixedpoint_begin transfers,
     // so the value is the result of the previous Secant update (xn_m1)
-    // Secondary: this is done after the secondary solve, but before timestep_end postprocessors
-    // are computed, or timestep_end transfers are received.
+    // Secondary: this is done after the secondary solve, but before fixedpoint_end postprocessors
+    // are computed, or fixedpoint_end transfers are received.
     // This value is the same as before the solve (xn_m1)
     (*transformed_pps_values)[i][1] = getPostprocessorValueByName((*transformed_pps)[i]);
   }
@@ -259,7 +259,7 @@ SecantSolve::printFixedPointConvergenceHistory()
   for (unsigned int i = 0; i <= _fixed_point_it; ++i)
   {
     Real max_norm =
-        std::max(_fixed_point_timestep_begin_norm[i], _fixed_point_timestep_end_norm[i]);
+        std::max(_fixed_point_begin_norm[i], _fixed_point_end_norm[i]);
     std::stringstream secant_prefix;
     if (i < 2)
       secant_prefix << " Secant initialization |R| = ";