[heap] New heuristics for incremental marking step size.

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 #include <map>
 
@@ skipping 1354 matching lines @@
 
   inline void UpdateNewSpaceAllocationCounter();
   inline size_t NewSpaceAllocationCounter();
 
   // This should be used only for testing.
   void set_new_space_allocation_counter(size_t new_value) {
     new_space_allocation_counter_ = new_value;
   }
 
   void UpdateOldGenerationAllocationCounter() {
-    old_generation_allocation_counter_ = OldGenerationAllocationCounter();
+    old_generation_allocation_counter_at_last_gc_ =
+        OldGenerationAllocationCounter();
   }
 
   size_t OldGenerationAllocationCounter() {
-    return old_generation_allocation_counter_ + PromotedSinceLastGC();
+    return old_generation_allocation_counter_at_last_gc_ +
+           PromotedSinceLastGC();
   }
 
   // This should be used only for testing.
-  void set_old_generation_allocation_counter(size_t new_value) {
-    old_generation_allocation_counter_ = new_value;
+  void set_old_generation_allocation_counter_at_last_gc(size_t new_value) {
+    old_generation_allocation_counter_at_last_gc_ = new_value;
   }
 
   size_t PromotedSinceLastGC() {
     return PromotedSpaceSizeOfObjects() - old_generation_size_at_last_gc_;
   }
 
   int gc_count() const { return gc_count_; }
 
   // Returns the size of objects residing in non new spaces.
   intptr_t PromotedSpaceSizeOfObjects();
@@ skipping 306 matching lines @@
 
   // Record statistics before and after garbage collection.
   void ReportStatisticsBeforeGC();
   void ReportStatisticsAfterGC();
 
   // Creates and installs the full-sized number string cache.
   int FullSizeNumberStringCacheLength();
   // Flush the number to string cache.
   void FlushNumberStringCache();
 
-  // TODO(hpayer): Allocation site pretenuring may make this method obsolete.
-  // Re-visit incremental marking heuristics.
-  bool IsHighSurvivalRate() { return high_survival_rate_period_length_ > 0; }
-
   void ConfigureInitialOldGenerationSize();
 
   bool HasLowYoungGenerationAllocationRate();
   bool HasLowOldGenerationAllocationRate();
   double YoungGenerationMutatorUtilization();
   double OldGenerationMutatorUtilization();
 
   void ReduceNewSpaceSize();
 
   GCIdleTimeHeapState ComputeHeapState();
@@ skipping 454 matching lines @@
   List<GCCallbackPair> gc_epilogue_callbacks_;
   List<GCCallbackPair> gc_prologue_callbacks_;
 
   // Total RegExp code ever generated
   double total_regexp_code_generated_;
 
   int deferred_counters_[v8::Isolate::kUseCounterFeatureCount];
 
   GCTracer* tracer_;
 
-  int high_survival_rate_period_length_;
   intptr_t promoted_objects_size_;
   double promotion_ratio_;
   double promotion_rate_;
   intptr_t semi_space_copied_object_size_;
   intptr_t previous_semi_space_copied_object_size_;
   double semi_space_copied_rate_;
   int nodes_died_in_new_space_;
   int nodes_copied_in_new_space_;
   int nodes_promoted_;
 
@@ skipping 38 matching lines @@
   size_t crankshaft_codegen_bytes_generated_;
 
   // This counter is increased before each GC and never reset.
   // To account for the bytes allocated since the last GC, use the
   // NewSpaceAllocationCounter() function.
   size_t new_space_allocation_counter_;
 
   // This counter is increased before each GC and never reset. To
   // account for the bytes allocated since the last GC, use the
   // OldGenerationAllocationCounter() function.
-  size_t old_generation_allocation_counter_;
+  size_t old_generation_allocation_counter_at_last_gc_;
 
   // The size of objects in old generation after the last MarkCompact GC.
   size_t old_generation_size_at_last_gc_;
 
   // If the --deopt_every_n_garbage_collections flag is set to a positive value,
   // this variable holds the number of garbage collections since the last
   // deoptimization triggered by garbage collection.
   int gcs_since_last_deopt_;
 
   // The feedback storage is used to store allocation sites (keys) and how often
@@ skipping 351 matching lines @@
   friend class LargeObjectSpace;
   friend class NewSpace;
   friend class PagedSpace;
   DISALLOW_COPY_AND_ASSIGN(AllocationObserver);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_HEAP_H_