reorganize routing flags, remove redundant trail compression flag

src/constraint_solver/constraint_solver.cc

@@ -75,6 +75,9 @@ DEFINE_bool(cp_use_cumulative_edge_finder, true,
             "Resources in O(kn log n)' by Petr Vilim, CP 2009.");
 DEFINE_bool(cp_use_cumulative_time_table, true,
             "Use a O(n^2) cumulative time table propagation algorithm.");
+DEFINE_bool(cp_use_cumulative_time_table_sync, false,
+            "Use a synchronized O(n^2 log n) cumulative time table propagation "
+            "algorithm.");
 DEFINE_bool(cp_use_sequence_high_demand_tasks, true,
             "Use a sequence constraints for cumulative tasks that have a "
             "demand greater than half of the capacity of the resource.");
@@ -139,6 +142,8 @@ ConstraintSolverParameters Solver::DefaultSolverParameters() {
   params.set_use_mdd_table(FLAGS_cp_use_mdd_table);
   params.set_use_cumulative_edge_finder(FLAGS_cp_use_cumulative_edge_finder);
   params.set_use_cumulative_time_table(FLAGS_cp_use_cumulative_time_table);
+  params.set_use_cumulative_time_table_sync(
+      FLAGS_cp_use_cumulative_time_table_sync);
   params.set_use_sequence_high_demand_tasks(
       FLAGS_cp_use_sequence_high_demand_tasks);
   params.set_use_all_possible_disjunctions(
@@ -1085,11 +1090,11 @@ class Search {
 #define CP_DO_FAIL(search) longjmp(search->fail_buffer_, 1)
 #else  // CP_USE_EXCEPTIONS_FOR_BACKTRACK
 class FailException {};
-#define CP_TRY(search)                                                 \
-  CHECK(!search->jmpbuf_filled_) << "Fail() called outside search";    \
-  search->jmpbuf_filled_ = true;                                       \
+#define CP_TRY(search)                                              \
+  CHECK(!search->jmpbuf_filled_) << "Fail() called outside search"; \
+  search->jmpbuf_filled_ = true;                                    \
   try
-#define CP_ON_FAIL catch(FailException&)
+#define CP_ON_FAIL catch (FailException&)
 #define CP_DO_FAIL(search) throw FailException()
 #endif  // CP_USE_EXCEPTIONS_FOR_BACKTRACK
 

src/constraint_solver/routing.cc

@@ -59,13 +59,6 @@ DEFINE_int64(sweep_sectors, 1,
              "The number of sectors the space is divided before it is sweeped "
              "by the ray.");
 
-// Cache settings.
-// TODO(user): Investigate if these settings could be moved to
-// RoutingSearchParameters or if we can get rid of them entirely.
-DEFINE_bool(routing_cache_callbacks, false, "Cache callback calls.");
-DEFINE_int64(routing_max_cache_size, 1000,
-             "Maximum cache size when callback caching is on.");
-
 // Trace settings
 
 // TODO(user): Move most of the following settings to a model parameter
@@ -1029,19 +1022,6 @@ class ConstantEvaluator : public BaseObject {
  private:
   const T value_;
 };
-
-ConstraintSolverParameters::TrailCompression GetTrailCompression(
-    RoutingModelParameters::TrailCompression trail_compression) {
-  switch (trail_compression) {
-    case RoutingModelParameters::NONE:
-      return ConstraintSolverParameters::NO_COMPRESSION;
-    case RoutingModelParameters::ZLIB:
-      return ConstraintSolverParameters::COMPRESS_WITH_ZLIB;
-    default:
-            return ConstraintSolverParameters::NO_COMPRESSION;
-  }
-}
-
 }  // namespace
 
 // ----- Routing model -----
@@ -1081,6 +1061,7 @@ RoutingModel::RoutingModel(int nodes, int vehicles,
       cost_classes_(),
       costs_are_homogeneous_across_vehicles_(
           parameters.reduce_vehicle_cost_model()),
+      cache_callbacks_(nodes <= parameters.max_callback_cache_size()),
       vehicle_class_index_of_vehicle_(vehicles_, VehicleClassIndex(-1)),
       starts_(vehicles),
       ends_(vehicles),
@@ -1099,8 +1080,6 @@ RoutingModel::RoutingModel(int nodes, int vehicles,
   ConstraintSolverParameters solver_parameters =
       parameters.has_solver_parameters() ? parameters.solver_parameters()
                                          : Solver::DefaultSolverParameters();
-  solver_parameters.set_compress_trail(
-      GetTrailCompression(parameters.trail_compression()));
   solver_.reset(new Solver("Routing", solver_parameters));
   InitializeBuilders(solver_.get());
   CHECK_EQ(vehicles, start_ends.size());
@@ -1133,6 +1112,7 @@ RoutingModel::RoutingModel(int nodes, int vehicles,
       cost_classes_(),
       costs_are_homogeneous_across_vehicles_(
           parameters.reduce_vehicle_cost_model()),
+      cache_callbacks_(nodes <= parameters.max_callback_cache_size()),
       vehicle_class_index_of_vehicle_(vehicles_, VehicleClassIndex(-1)),
       starts_(vehicles),
       ends_(vehicles),
@@ -1151,8 +1131,6 @@ RoutingModel::RoutingModel(int nodes, int vehicles,
   ConstraintSolverParameters solver_parameters =
       parameters.has_solver_parameters() ? parameters.solver_parameters()
                                          : Solver::DefaultSolverParameters();
-  solver_parameters.set_compress_trail(
-      GetTrailCompression(parameters.trail_compression()));
   solver_.reset(new Solver("Routing", solver_parameters));
   InitializeBuilders(solver_.get());
   CHECK_EQ(vehicles, starts.size());
@@ -1210,13 +1188,13 @@ RoutingModel::~RoutingModel() {
 }
 
 RoutingModelParameters RoutingModel::DefaultModelParameters() {
-  static const char* const kModelParameters =
-      "reduce_vehicle_cost_model: true "
-            "trail_compression: ZLIB";
   RoutingModelParameters parameters;
-  if (!google::protobuf::TextFormat::ParseFromString(kModelParameters, &parameters)) {
-    LOG(ERROR) << "Unsupported default model parameters: " << kModelParameters;
-  }
+  ConstraintSolverParameters* const solver_parameters =
+      parameters.mutable_solver_parameters();
+  *solver_parameters = Solver::DefaultSolverParameters();
+  solver_parameters->set_compress_trail(
+         ConstraintSolverParameters::COMPRESS_WITH_ZLIB);
+  parameters.set_reduce_vehicle_cost_model(true);
   return parameters;
 }
 
@@ -4880,7 +4858,7 @@ void RoutingModel::AddIntervalToAssignment(IntervalVar* const interval) {
 RoutingModel::NodeEvaluator2* RoutingModel::NewCachedCallback(
     NodeEvaluator2* callback) {
   const int size = node_to_index_.size();
-  if (FLAGS_routing_cache_callbacks && size <= FLAGS_routing_max_cache_size) {
+  if (cache_callbacks_) {
     NodeEvaluator2* cached_evaluator = nullptr;
     if (!FindCopy(cached_node_callbacks_, callback, &cached_evaluator)) {
       cached_evaluator = new RoutingCache(callback, size);

src/constraint_solver/routing.h

@@ -1231,6 +1231,7 @@ class RoutingModel {
   ITIVector<CostClassIndex, CostClass> cost_classes_;
 #endif  // SWIG
   bool costs_are_homogeneous_across_vehicles_;
+  bool cache_callbacks_;
   std::vector<CostCacheElement> cost_cache_;  // Index by source index.
   std::vector<VehicleClassIndex> vehicle_class_index_of_vehicle_;
 #ifndef SWIG

src/constraint_solver/routing_flags.cc

@@ -17,6 +17,7 @@
 #include <vector>
 
 #include "base/map_util.h"
+#include "constraint_solver/constraint_solver.h"
 
 // --- Routing search flags ---
 
@@ -78,6 +79,11 @@ DEFINE_int64(routing_optimization_step, 1, "Optimization step.");
 DEFINE_bool(routing_use_light_propagation, true,
             "Use constraints with light propagation in routing model.");
 
+// Cache settings.
+DEFINE_bool(routing_cache_callbacks, false, "Cache callback calls.");
+DEFINE_int64(routing_max_cache_size, 1000,
+             "Maximum cache size when callback caching is on.");
+
 // Misc
 DEFINE_bool(routing_fingerprint_arc_cost_evaluators, true,
             "Compare arc-cost evaluators using the fingerprint of their "
@@ -197,7 +203,13 @@ RoutingSearchParameters BuildSearchParametersFromFlags() {
 
 RoutingModelParameters BuildModelParametersFromFlags() {
   RoutingModelParameters parameters;
+  ConstraintSolverParameters* const solver_parameters =
+      parameters.mutable_solver_parameters();
+  *solver_parameters = Solver::DefaultSolverParameters();
   parameters.set_reduce_vehicle_cost_model(FLAGS_routing_use_homogeneous_costs);
+  if (FLAGS_routing_cache_callbacks) {
+    parameters.set_max_callback_cache_size(FLAGS_routing_max_cache_size);
+  }
   return parameters;
 }
 }  // namespace operations_research

src/constraint_solver/routing_flags.h

@@ -57,6 +57,10 @@ DECLARE_int64(routing_optimization_step);
 // Propagation control
 DECLARE_bool(routing_use_light_propagation);
 
+// Cache settings.
+DECLARE_bool(routing_cache_callbacks);
+DECLARE_int64(routing_max_cache_size);
+
 // Misc
 DECLARE_bool(routing_fingerprint_arc_cost_evaluators);
 DECLARE_bool(routing_trace);

src/constraint_solver/routing_parameters.proto

@@ -262,20 +262,14 @@ message RoutingSearchParameters {
 
 // Parameters which have to be set when creating a RoutingModel.
 message RoutingModelParameters {
+  // Parameters to use in the underlying constraint solver.
+  ConstraintSolverParameters solver_parameters = 1;
   // Advanced settings.
   // If set to true reduction of the underlying constraint model will be
   // attempted when all vehicles have exactly the same cost structure. This can
   // result in significant speedups.
-  bool reduce_vehicle_cost_model = 1;
-  // Algorithm to use to compress the constraint solver trail.
-  // TODO(user): This field is obsolete as it is redudant with the
-  // solver_parameters field which contains trail compression settings.
-  // Remove it.
-  enum TrailCompression {
-    NONE = 0;
-    ZLIB = 1;
-  }
-  TrailCompression trail_compression = 2;
-  // Parameters to use in the underlying constraint solver.
-  ConstraintSolverParameters solver_parameters = 3;
+  bool reduce_vehicle_cost_model = 2;
+  // Cache callback calls if the number of nodes in the model is less or equal
+  // to this value.
+  int32 max_callback_cache_size = 3;
 }