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src/callbacks_step/alive.jl

@@ -75,6 +75,8 @@ end
 
 # this method is called when the callback is activated
 function (alive_callback::AliveCallback)(integrator)
+
+    println("Start of alive callback")
     # Checking for floating point equality is OK here as `DifferentialEquations.jl`
     # sets the time exactly to the final time in the last iteration
     if isfinished(integrator) && mpi_isroot()
@@ -98,6 +100,8 @@ function (alive_callback::AliveCallback)(integrator)
 
     # avoid re-evaluating possible FSAL stages
     u_modified!(integrator, false)
+
+    println("End of alive callback")
     return nothing
 end
 end # @muladd

src/callbacks_step/stepsize.jl

@@ -59,6 +59,7 @@ end
 
 # This method is called as callback during the time integration.
 @inline function (stepsize_callback::StepsizeCallback)(integrator)
+    println("Start of stepsize_callback")
     # TODO: Taal decide, shall we set the time step even if the integrator is adaptive?
     if !integrator.opts.adaptive
         t = integrator.t
@@ -77,6 +78,7 @@ end
 
     # avoid re-evaluating possible FSAL stages
     u_modified!(integrator, false)
+    println("End of stepsize_callback")
     return nothing
 end