Only pass idle notifications on from the API if V8 has been...

src/heap.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2767 matching lines @@
   int size = map->instance_size();
   AllocationSpace space =
       (size > MaxObjectSizeInPagedSpace()) ? LO_SPACE : OLD_POINTER_SPACE;
   Object* result = Heap::Allocate(map, space);
   if (result->IsFailure()) return result;
   Struct::cast(result)->InitializeBody(size);
   return result;
 }
 
 
+bool Heap::IdleNotification() {
+  static const int kIdlesBeforeCollection = 7;
+  static int number_idle_notifications = 0;
+  static int last_gc_count = gc_count_;
+
+  bool finished = false;
+
+  if (last_gc_count == gc_count_) {
+    number_idle_notifications++;
+  } else {
+    number_idle_notifications = 0;
+    last_gc_count = gc_count_;
+  }
+
+  if (number_idle_notifications >= kIdlesBeforeCollection) {
+    // The first time through we collect without forcing compaction.
+    // The second time through we force compaction and quit.
+    bool force_compaction =
+        number_idle_notifications > kIdlesBeforeCollection;
+    CollectAllGarbage(force_compaction);
+    last_gc_count = gc_count_;
+    if (force_compaction) {
+      number_idle_notifications = 0;
+      finished = true;
+    }
+  }
+
+  // Uncommit unused memory in new space.
+  Heap::UncommitFromSpace();
+  return finished;
+}
+
+
 #ifdef DEBUG
 
 void Heap::Print() {
   if (!HasBeenSetup()) return;
   Top::PrintStack();
   AllSpaces spaces;
   while (Space* space = spaces.next()) space->Print();
 }
 
 
@@ skipping 1128 matching lines @@
 #ifdef DEBUG
 bool Heap::GarbageCollectionGreedyCheck() {
   ASSERT(FLAG_gc_greedy);
   if (Bootstrapper::IsActive()) return true;
   if (disallow_allocation_failure()) return true;
   return CollectGarbage(0, NEW_SPACE);
 }
 #endif
 
 } }  // namespace v8::internal