printf debugging...

src/hydro/hydro.cpp

@@ -873,6 +873,8 @@ Real EstimateTimestep(MeshData<Real> *md) {
     auto dt_diff_param = hydro_pkg->Param<Real>("dt_diff");
     hydro_pkg->UpdateParam("dt_diff", std::min(dt_diff, dt_diff_param));
   }
+  std::cerr << "[" << parthenon::Globals::my_rank << "]  DT:\ttau=" << dt_hyp
+            << " dt_diff=" << dt_diff << "\n";
 
   if (ProblemEstimateTimestep != nullptr) {
     min_dt = std::min(min_dt, ProblemEstimateTimestep(md));

src/hydro/hydro_driver.cpp

@@ -13,6 +13,7 @@
 // Parthenon headers
 #include "amr_criteria/refinement_package.hpp"
 #include "bvals/comms/bvals_in_one.hpp"
+#include "globals.hpp"
 #include "prolong_restrict/prolong_restrict.hpp"
 #include <parthenon/parthenon.hpp>
 // AthenaPK headers
@@ -218,6 +219,9 @@ void AddSTSTasks(TaskCollection *ptask_coll, Mesh *pmesh, BlockList_t &blocks,
   // ensure odd number of stages
   if (s_rkl % 2 == 0) s_rkl += 1;
 
+  std::cerr << "[" << parthenon::Globals::my_rank << "] STS:\ttau=" << tau
+            << " dt_diff=" << mindt_diff << "\n";
+
   if (parthenon::Globals::my_rank == 0) {
     const auto ratio = 2.0 * tau / mindt_diff;
     std::cout << "STS ratio: " << ratio << " Taking " << s_rkl << " steps." << std::endl;
@@ -481,6 +485,8 @@ TaskCollection HydroDriver::MakeTaskCollection(BlockList_t &blocks, int stage) {
           hydro_pkg->UpdateParam("mindx", mins[0]);
           hydro_pkg->UpdateParam("dt_hyp", mins[1]);
           hydro_pkg->UpdateParam("dt_diff", mins[2]);
+          std::cerr << "[" << parthenon::Globals::my_rank << "] INI:\ttau=" << mins[1]
+                    << " dt_diff=" << mins[2] << "\n";
           return TaskStatus::complete;
         },
         hydro_pkg.get());