Add histograms for idle notification and incremental marking steps

src/heap.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/base/once.h"
 #include "src/base/utils/random-number-generator.h"
@@ skipping 4209 matching lines @@
 void Heap::MakeHeapIterable() {
   ASSERT(AllowHeapAllocation::IsAllowed());
   if (!IsHeapIterable()) {
     CollectAllGarbage(kMakeHeapIterableMask, "Heap::MakeHeapIterable");
   }
   ASSERT(IsHeapIterable());
 }
 
 
 void Heap::AdvanceIdleIncrementalMarking(intptr_t step_size) {
+  HistogramTimerScope idle_notification_scope(
+      isolate_->counters()->gc_incremental_marking());
+
   incremental_marking()->Step(step_size,
                               IncrementalMarking::NO_GC_VIA_STACK_GUARD);
 
   if (incremental_marking()->IsComplete()) {
     bool uncommit = false;
     if (gc_count_at_last_idle_gc_ == gc_count_) {
       // No GC since the last full GC, the mutator is probably not active.
       isolate_->compilation_cache()->Clear();
       uncommit = true;
     }
@@ skipping 16 matching lines @@
   const int kMinHintForIncrementalMarking = 10;
   // Minimal hint that allows to do full GC.
   const int kMinHintForFullGC = 100;
   intptr_t size_factor = Min(Max(hint, 20), kMaxHint) / 4;
   // The size factor is in range [5..250]. The numbers here are chosen from
   // experiments. If you changes them, make sure to test with
   // chrome/performance_ui_tests --gtest_filter="GeneralMixMemoryTest.*
   intptr_t step_size =
       size_factor * IncrementalMarking::kAllocatedThreshold;
 
+  HistogramTimerScope idle_notification_scope(
+      isolate_->counters()->gc_idle_notification());
+
   if (contexts_disposed_ > 0) {
     contexts_disposed_ = 0;
     int mark_sweep_time = Min(TimeMarkSweepWouldTakeInMs(), 1000);
     if (hint >= mark_sweep_time && !FLAG_expose_gc &&
         incremental_marking()->IsStopped()) {
       HistogramTimerScope scope(isolate_->counters()->gc_context());
       CollectAllGarbage(kReduceMemoryFootprintMask,
                         "idle notification: contexts disposed");
     } else {
       AdvanceIdleIncrementalMarking(step_size);
@@ skipping 2150 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   CODE_AGE_LIST_COMPLETE(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   MemCopy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   MemCopy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal