added out of memory handling

src/generator/CMakeLists.txt

@@ -11,8 +11,9 @@ file(GLOB_RECURSE GENERATOR_PUBLIC_HEADER_FILES
 target_sources(dlplangenerator
     PRIVATE
         ${GENERATOR_SRC_FILES} ${GENERATOR_PRIVATE_HEADER_FILES} ${GENERATOR_PUBLIC_HEADER_FILES}
-        ../utils/logging.cpp
-        ../utils/countdown_timer.cpp
+        "../utils/logging.h" "../utils/logging.cpp"
+        "../utils/countdown_timer.h" "../utils/countdown_timer.cpp"
+        "../utils/memory.h" "../utils/memory.cpp"
 )
 target_link_libraries(dlplangenerator
     PUBLIC

src/generator/generator.cpp

@@ -1,6 +1,7 @@
 #include "../../include/dlplan/generator.h"
 
 #include "feature_generator.h"
+#include "../utils/memory.h"
 
 
 namespace dlplan::generator {
@@ -37,7 +38,14 @@ GeneratedFeatures FeatureGenerator::generate(
     int distance_numerical_complexity_limit,
     int time_limit,
     int feature_limit) {
-    return m_pImpl->generate(factory, states, concept_complexity_limit, role_complexity_limit, boolean_complexity_limit, count_numerical_complexity_limit, distance_numerical_complexity_limit, time_limit, feature_limit);
+
+    utils::reserve_extra_memory_padding(1);
+
+    auto features = m_pImpl->generate(factory, states, concept_complexity_limit, role_complexity_limit, boolean_complexity_limit, count_numerical_complexity_limit, distance_numerical_complexity_limit, time_limit, feature_limit);
+
+    utils::release_extra_memory_padding();
+
+    return features;
 }
 
 void FeatureGenerator::set_generate_empty_boolean(bool enable) {

src/state_space/CMakeLists.txt

@@ -11,6 +11,7 @@ file(GLOB_RECURSE STATE_SPACE_PUBLIC_HEADER_FILES
 target_sources(dlplanstatespace
     PRIVATE
         ${STATE_SPACE_SRC_FILES} ${STATE_SPACE_PRIVATE_HEADER_FILES} ${STATE_SPACE_PUBLIC_HEADER_FILES}
+        "../utils/memory.h" "../utils/memory.cpp"
 )
 
 target_link_libraries(dlplanstatespace

src/state_space/state_space.cpp

@@ -356,8 +356,15 @@ GeneratorResult generate_state_space(
     core::InstanceIndex index,
     int max_time,
     int max_num_states) {
+
+    utils::reserve_extra_memory_padding(1);
+
     generator::generate_state_space_files(domain_file, instance_file, max_time, max_num_states);
-    return reader::read(vocabulary_info, index);
+    auto result = reader::read(vocabulary_info, index);
+
+    utils::release_extra_memory_padding();
+
+    return result;
 }
 
 }

src/utils/memory.cpp

@@ -0,0 +1,34 @@
+#include "memory.h"
+
+#include <cassert>
+#include <iostream>
+
+namespace dlplan::utils {
+static char *extra_memory_padding = nullptr;
+
+// Save standard out-of-memory handler.
+static void (*standard_out_of_memory_handler)() = nullptr;
+
+static void continuing_out_of_memory_handler() {
+    release_extra_memory_padding();
+    std::cout << "Failed to allocate memory. Released extra memory padding." << std::endl;
+}
+
+void reserve_extra_memory_padding(int memory_in_mb) {
+    assert(!extra_memory_padding);
+    extra_memory_padding = new char[memory_in_mb * 1024 * 1024];
+    standard_out_of_memory_handler = std::set_new_handler(continuing_out_of_memory_handler);
+}
+
+void release_extra_memory_padding() {
+    assert(extra_memory_padding);
+    delete[] extra_memory_padding;
+    extra_memory_padding = nullptr;
+    assert(standard_out_of_memory_handler);
+    std::set_new_handler(standard_out_of_memory_handler);
+}
+
+bool extra_memory_padding_is_reserved() {
+    return extra_memory_padding;
+}
+}

src/utils/memory.h

@@ -1,17 +1,26 @@
 #ifndef DLPLAN_SRC_UTILS_MEMORY_H
 #define DLPLAN_SRC_UTILS_MEMORY_H
 
+#include <memory>
+#include <utility>
 
 namespace dlplan::utils {
 
-/**
- * Uses swap-trick to free memory of container.
- */
-template<typename CONTAINER_TYPE>
-void free_memory(CONTAINER_TYPE& container) {
-    CONTAINER_TYPE().swap(container);
-}
+/*
+  Taken from Fast-Downward (https://www.fast-downward.org/)
+
+  Reserve some memory that we can release and be able to continue
+  afterwards, once we hit the memory limit. Due to memory fragmentation
+  the planner often doesn't have enough memory to continue if we don't
+  reserve enough memory. For CEGAR heuristics reserving 75 MB worked
+  best.
 
+  The interface assumes a single user. It is not possible for two parts
+  of the planner to reserve extra memory padding at the same time.
+*/
+extern void reserve_extra_memory_padding(int memory_in_mb);
+extern void release_extra_memory_padding();
+extern bool extra_memory_padding_is_reserved();
 }
 
 #endif