Made aborting the step at growing residual optional

pySDC/implementations/convergence_controller_classes/adaptivity.py

@@ -208,6 +208,7 @@ def setup(self, controller, params, description, **kwargs):
             'residual_max_tol': 1e9,
             'maxiter': description['sweeper_params'].get('maxiter', 99),
             'interpolate_between_restarts': True,
+            'abort_at_growing_residual': True,
             **super().setup(controller, params, description, **kwargs),
         }
         if defaults['restol_rel']:
@@ -232,7 +233,12 @@ def determine_restart(self, controller, S, **kwargs):
                 self.trigger_restart_upon_nonconvergence(S)
             elif self.get_local_error_estimate(controller, S, **kwargs) > self.params.e_tol:
                 S.status.restart = True
-        elif S.status.time_size == 1 and self.res_last_iter < S.levels[0].status.residual and S.status.iter > 0:
+        elif (
+            S.status.time_size == 1
+            and self.res_last_iter < S.levels[0].status.residual
+            and S.status.iter > 0
+            and self.params.abort_at_growing_residual
+        ):
             self.trigger_restart_upon_nonconvergence(S)
         elif S.levels[0].status.residual > self.params.residual_max_tol:
             self.trigger_restart_upon_nonconvergence(S)