Enable logging of Solver logs to files.

schedulers/tetrisched/include/tetrisched/CPLEXSolver.hpp

@@ -51,6 +51,9 @@ class CPLEXSolver : public Solver {
   /// Export the constructed model to the given file.
   void exportModel(const std::string& fileName) override;
 
+  /// Set the log file for the solver to output its log to.
+  void setLogFile(const std::string& fileName) override;
+
   /// Solve the constructed model.
   SolverSolutionPtr solveModel() override;
 

schedulers/tetrisched/include/tetrisched/GoogleCPSolver.hpp

@@ -50,6 +50,9 @@ class GoogleCPSolver : public Solver {
   /// Export the constructed model to the given file.
   void exportModel(const std::string& fileName) override;
 
+  /// Set the log file for the solver to output its log to.
+  void setLogFile(const std::string& fileName) override;
+
   /// Solve the constructed model.
   SolverSolutionPtr solveModel() override;
 

schedulers/tetrisched/include/tetrisched/GurobiSolver.hpp

@@ -16,9 +16,11 @@ class GurobiSolver : public Solver {
   /// A map from the ID of the SolverModel variables to internal Gurobi
   /// variables.
   std::unordered_map<uint32_t, GRBVar> gurobiVariables;
+  /// The name of the log file for the Gurobi solving.
+  std::string logFileName;
 
   /// Set the defaults for parameters on the model.
-  void setDefaultParameters(GRBModel& gurobiModel);
+  void setParameters(GRBModel& gurobiModel);
 
   /// Translate the variable to a Gurobi variable.
   GRBVar translateVariable(GRBModel& gurobiModel,
@@ -51,6 +53,9 @@ class GurobiSolver : public Solver {
   /// Export the constructed model to the given file.
   void exportModel(const std::string& fileName) override;
 
+  /// Set the log file for the solver to output its log to.
+  void setLogFile(const std::string& fileName) override;
+
   /// Solve the constructed model.
   SolverSolutionPtr solveModel() override;
 

schedulers/tetrisched/include/tetrisched/Solver.hpp

@@ -87,6 +87,9 @@ class Solver {
   /// Export the constructed model to the given file.
   virtual void exportModel(const std::string& fileName) = 0;
 
+  /// Set the log file for the solver to output its log to.
+  virtual void setLogFile(const std::string& fileName) = 0;
+
   /// Solve the constructed model.
   virtual SolverSolutionPtr solveModel() = 0;
 

schedulers/tetrisched/src/CPLEXSolver.cpp

@@ -201,6 +201,11 @@ void CPLEXSolver::exportModel(const std::string& fname) {
   cplexInstance.exportModel(fname.c_str());
 }
 
+void CPLEXSolver::setLogFile(const std::string& fname) {
+  throw tetrisched::exceptions::SolverException(
+      "setLogFile() not implemented for CPLEXSolver.");
+}
+
 SolverSolutionPtr CPLEXSolver::solveModel() {
   // Create the result object.
   SolverSolutionPtr solverSolution = std::make_shared<SolverSolution>();

schedulers/tetrisched/src/GoogleCPSolver.cpp

@@ -166,6 +166,11 @@ void GoogleCPSolver::exportModel(const std::string& fileName) {
   cpModel->ExportToFile(fileName);
 }
 
+void GoogleCPSolver::setLogFile(const std::string& fname) {
+  throw tetrisched::exceptions::SolverException(
+      "setLogFile() not implemented for GoogleCPSolver.");
+}
+
 SolverSolutionPtr GoogleCPSolver::solveModel() {
   throw exceptions::SolverException("Not implemented yet!");
 }

schedulers/tetrisched/src/GurobiSolver.cpp

@@ -5,8 +5,10 @@
 
 namespace tetrisched {
 GurobiSolver::GurobiSolver()
-    : gurobiEnv(new GRBEnv()), gurobiModel(new GRBModel(*gurobiEnv)) {
-  setDefaultParameters(*gurobiModel);
+    : gurobiEnv(new GRBEnv()),
+      gurobiModel(new GRBModel(*gurobiEnv)),
+      logFileName("") {
+  setParameters(*gurobiModel);
 }
 
 SolverModelPtr GurobiSolver::getModel() {
@@ -20,16 +22,24 @@ void GurobiSolver::setModel(SolverModelPtr solverModelPtr) {
   solverModel = solverModelPtr;
 }
 
-void GurobiSolver::setDefaultParameters(GRBModel& gurobiModel) {
+void GurobiSolver::setParameters(GRBModel& gurobiModel) {
   // Set the maximum numer of threads.
   const auto thread_count = std::thread::hardware_concurrency();
   gurobiModel.set(GRB_IntParam_Threads, thread_count);
 
   // Ask Gurobi to aggressively cut the search space.
   gurobiModel.set(GRB_IntParam_Cuts, 3);
 
+  // Ask Gurobi to aggressively presolve the model.
+  gurobiModel.set(GRB_IntParam_Presolve, 2);
+
   // Ask Gurobi to find new incumbent solutions rather than prove bounds.
   gurobiModel.set(GRB_IntParam_MIPFocus, 1);
+
+  // Ask Gurobi to not output to the console, and instead direct it
+  // to the specified file.
+  // gurobiModel.set(GRB_IntParam_LogToConsole, 0);
+  gurobiModel.set(GRB_StringParam_LogFile, logFileName);
 }
 
 GRBVar GurobiSolver::translateVariable(GRBModel& gurobiModel,
@@ -144,7 +154,7 @@ void GurobiSolver::translateModel() {
   }
 
   gurobiModel = std::make_unique<GRBModel>(*gurobiEnv);
-  setDefaultParameters(*gurobiModel);
+  setParameters(*gurobiModel);
 
   // Generate all the variables and keep a cache of the variable indices
   // to the Gurobi variables.
@@ -183,6 +193,10 @@ void GurobiSolver::exportModel(const std::string& fileName) {
   gurobiModel->write(fileName);
 }
 
+void GurobiSolver::setLogFile(const std::string& fileName) {
+  logFileName = fileName;
+}
+
 SolverSolutionPtr GurobiSolver::solveModel() {
   // Create the result object.
   SolverSolutionPtr solverSolution = std::make_shared<SolverSolution>();

schedulers/tetrisched/src/Scheduler.cpp

@@ -60,6 +60,10 @@ void Scheduler::schedule(Time currentTime) {
         "Please invoke registerSTRL() first.");
   }
 
+  // Set the log file based on the current time.
+  std::string logFileName = "tetrisched_" + std::to_string(currentTime) + ".log";
+  this->solver->setLogFile(logFileName);
+
   // Translate the model to the solver backend.
   this->solver->translateModel();