Start incremental marking on idle notification.

src/heap.h

 // Copyright 2011 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 1409 matching lines @@
   void QueueMemoryChunkForFree(MemoryChunk* chunk);
   void FreeQueuedChunks();
 
   // Completely clear the Instanceof cache (to stop it keeping objects alive
   // around a GC).
   inline void CompletelyClearInstanceofCache();
 
   // The roots that have an index less than this are always in old space.
   static const int kOldSpaceRoots = 0x20;
 
+  bool idle_notification_will_schedule_next_gc() {
+    return idle_notification_will_schedule_next_gc_;
+  }
+
  private:
   Heap();
 
   // This can be calculated directly from a pointer to the heap; however, it is
   // more expedient to get at the isolate directly from within Heap methods.
   Isolate* isolate_;
 
   intptr_t code_range_size_;
   int reserved_semispace_size_;
   int max_semispace_size_;
@@ skipping 305 matching lines @@
   bool IsIncreasingSurvivalTrend() {
     return survival_rate_trend() == INCREASING;
   }
 
   bool IsHighSurvivalRate() {
     return high_survival_rate_period_length_ > 0;
   }
 
   void SelectScavengingVisitorsTable();
 
+  bool WorthStartingGCWhenIdle() {
+    if (contexts_disposed_ > 0) {
+      return true;
+    }
+    if (number_idle_notifications_ < kMaxIdleCount) {
+      return incremental_marking()->WorthActivating();
+    }
+    if (gc_count_ - last_idle_notification_gc_count_ > kGCsBetweenCleanup) {
+      return incremental_marking()->WorthActivating() &&
+             NextGCIsLikelyToBeFull();
+    }
+    return false;
+  }
+
+  // Returns true if no more GC work is left.
+  bool IdleGlobalGC();
+
   static const int kInitialSymbolTableSize = 2048;
   static const int kInitialEvalCacheSize = 64;
 
   // Maximum GC pause.
   int max_gc_pause_;
 
   // Maximum size of objects alive after GC.
   intptr_t max_alive_after_gc_;
 
   // Minimal interval between two subsequent collections.
   int min_in_mutator_;
 
   // Size of objects alive after last GC.
   intptr_t alive_after_last_gc_;
 
   double last_gc_end_timestamp_;
 
   MarkCompactCollector mark_compact_collector_;
 
   StoreBuffer store_buffer_;
 
   Marking marking_;
 
   IncrementalMarking incremental_marking_;
 
+  static const int kIdlesBeforeScavenge = 4;
+  static const int kIdlesBeforeMarkSweep = 7;
+  static const int kIdlesBeforeMarkCompact = 8;
+  static const int kMaxIdleCount = kIdlesBeforeMarkCompact + 1;

[Erik Corry, 2011/11/10 15:06:55]

The name kMaxIdleCount no longer makes much sense.  Can't we get any more idle
notifications than this, and why not?

[ulan, 2011/11/11 13:27:26]

Now I don't use this constant in the new IdleNotification.

+  static const unsigned int kGCsBetweenCleanup = 4;

[Erik Corry, 2011/11/10 15:06:55]

I suggest kScavengesBeforeFullGC for this one.

[ulan, 2011/11/11 13:27:26]

Ditto.

+
   int number_idle_notifications_;
   unsigned int last_idle_notification_gc_count_;
   bool last_idle_notification_gc_count_init_;
+  bool idle_notification_will_schedule_next_gc_;
+  double last_idle_notification_timestamp_;
+
 
   // Shared state read by the scavenge collector and set by ScavengeObject.
   PromotionQueue promotion_queue_;
 
   // Flag is set when the heap has been configured.  The heap can be repeatedly
   // configured through the API until it is setup.
   bool configured_;
 
   ExternalStringTable external_string_table_;
 
@@ skipping 685 matching lines @@
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #undef HEAP
 
 #endif  // V8_HEAP_H_