Limit rate of full garbage collections triggered by idle notification.

src/heap/gc-idle-time-handler.h

Index: src/heap/gc-idle-time-handler.h
diff --git a/src/heap/gc-idle-time-handler.h b/src/heap/gc-idle-time-handler.h
index 6a39b78aaa2fcc24fd5210236f177bf0f9fffc14..e75e4a0ffa1b4e7e04b71a432aa072341af473ec 100644
--- a/src/heap/gc-idle-time-handler.h
+++ b/src/heap/gc-idle-time-handler.h
@@ -136,8 +136,15 @@ class GCIdleTimeHandler {
   // Incremental marking step time.
   static const size_t kIncrementalMarkingStepTimeInMs = 1;
 
+  // This is the minimum time required to perform over approximation of
+  // weak closure during idle notification.
   static const size_t kMinTimeForOverApproximatingWeakClosureInMs;
 
+  // No full garbage collections are performed if the last full GC was done
+  // kMinTimeInBetweenMarkCompactsInMs milliseconds before. Idle times larger
+  // than kMaxScheduledIdleTime ignore that threshold.
+  static const size_t kMinTimeInBetweenMarkCompactsInMs = 1000;

[rmcilroy, 2015/03/20 14:56:08]

Is 1000ms a guesstimation or is there any reason to think that pages shouldn't
really need full GCs within 1s?

+
   class HeapState {
    public:
     void Print();
@@ -155,6 +162,8 @@ class GCIdleTimeHandler {
     size_t used_new_space_size;
     size_t new_space_capacity;
     size_t new_space_allocation_throughput_in_bytes_per_ms;
+    size_t last_mark_compact_time;
+    size_t current_time;
   };
 
   GCIdleTimeHandler()
@@ -186,7 +195,9 @@ class GCIdleTimeHandler {
 
   static bool ShouldDoMarkCompact(size_t idle_time_in_ms,
                                   size_t size_of_objects,
-                                  size_t mark_compact_speed_in_bytes_per_ms);
+                                  size_t mark_compact_speed_in_bytes_per_ms,
+                                  size_t last_mark_compact_time_in_ms,
+                                  size_t current_time_in_ms);
 
   static bool ShouldDoContextDisposalMarkCompact(int context_disposed,
                                                  double contexts_disposal_rate);