Measure new space allocation throughput.

BUG=
R=ulan@chromium.org

Review URL: https://codereview.chromium.org/578453003

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23994 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap/gc-tracer.cc

@@ -19,6 +19,13 @@ static intptr_t CountTotalHolesSize(Heap* heap) {
 }
 
 
+GCTracer::AllocationEvent::AllocationEvent(double duration,
+                                           intptr_t allocation_in_bytes) {
+  duration_ = duration;
+  allocation_in_bytes_ = allocation_in_bytes;
+}
+
+
 GCTracer::Event::Event(Type type, const char* gc_reason,
                        const char* collector_reason)
     : type(type),
@@ -80,7 +87,8 @@ GCTracer::GCTracer(Heap* heap)
       cumulative_pure_incremental_marking_duration_(0.0),
       longest_incremental_marking_step_(0.0),
       cumulative_marking_duration_(0.0),
-      cumulative_sweeping_duration_(0.0) {
+      cumulative_sweeping_duration_(0.0),
+      new_space_top_after_gc_(0) {
   current_ = Event(Event::START, NULL, NULL);
   current_.end_time = base::OS::TimeCurrentMillis();
   previous_ = previous_mark_compactor_event_ = current_;
@@ -90,6 +98,13 @@ GCTracer::GCTracer(Heap* heap)
 void GCTracer::Start(GarbageCollector collector, const char* gc_reason,
                      const char* collector_reason) {
   previous_ = current_;
+  double start_time = base::OS::TimeCurrentMillis();
+  if (new_space_top_after_gc_ != 0) {
+    AddNewSpaceAllocationTime(
+        start_time - previous_.end_time,
+        reinterpret_cast<intptr_t>((heap_->new_space()->top()) -
+                                   new_space_top_after_gc_));
+  }
   if (current_.type == Event::MARK_COMPACTOR)
     previous_mark_compactor_event_ = current_;
 
@@ -99,7 +114,7 @@ void GCTracer::Start(GarbageCollector collector, const char* gc_reason,
     current_ = Event(Event::MARK_COMPACTOR, gc_reason, collector_reason);
   }
 
-  current_.start_time = base::OS::TimeCurrentMillis();
+  current_.start_time = start_time;
   current_.start_object_size = heap_->SizeOfObjects();
   current_.start_memory_size = heap_->isolate()->memory_allocator()->Size();
   current_.start_holes_size = CountTotalHolesSize(heap_);
@@ -127,6 +142,8 @@ void GCTracer::Stop() {
   current_.end_object_size = heap_->SizeOfObjects();
   current_.end_memory_size = heap_->isolate()->memory_allocator()->Size();
   current_.end_holes_size = CountTotalHolesSize(heap_);
+  new_space_top_after_gc_ =
+      reinterpret_cast<intptr_t>(heap_->new_space()->top());
 
   if (current_.type == Event::SCAVENGER) {
     current_.incremental_marking_steps =
@@ -184,6 +201,12 @@ void GCTracer::Stop() {
 }
 
 
+void GCTracer::AddNewSpaceAllocationTime(double duration,
+                                         intptr_t allocation_in_bytes) {
+  allocation_events_.push_front(AllocationEvent(duration, allocation_in_bytes));
+}
+
+
 void GCTracer::AddIncrementalMarkingStep(double duration, intptr_t bytes) {
   cumulative_incremental_marking_steps_++;
   cumulative_incremental_marking_bytes_ += bytes;
@@ -294,6 +317,8 @@ void GCTracer::PrintNVP() const {
   PrintF("nodes_promoted=%d ", heap_->nodes_promoted_);
   PrintF("promotion_rate=%.1f%% ", heap_->promotion_rate_);
   PrintF("semi_space_copy_rate=%.1f%% ", heap_->semi_space_copied_rate_);
+  PrintF("new_space_allocation_throughput=%d ",
+         NewSpaceAllocationThroughputInBytesPerMillisecond());
 
   if (current_.type == Event::SCAVENGER) {
     PrintF("steps_count=%d ", current_.incremental_marking_steps);
@@ -435,5 +460,21 @@ intptr_t GCTracer::MarkCompactSpeedInBytesPerMillisecond() const {
 
   return static_cast<intptr_t>(bytes / durations);
 }
+
+
+intptr_t GCTracer::NewSpaceAllocationThroughputInBytesPerMillisecond() const {
+  intptr_t bytes = 0;
+  double durations = 0.0;
+  AllocationEventBuffer::const_iterator iter = allocation_events_.begin();
+  while (iter != allocation_events_.end()) {
+    bytes += iter->allocation_in_bytes_;
+    durations += iter->duration_;
+    ++iter;
+  }
+
+  if (durations == 0.0) return 0;
+
+  return static_cast<intptr_t>(bytes / durations);
+}
 }
 }  // namespace v8::internal

src/heap/gc-tracer.h

@@ -129,6 +129,22 @@ class GCTracer {
   };
 
 
+  class AllocationEvent {
+   public:
+    // Default constructor leaves the event uninitialized.
+    AllocationEvent() {}
+
+    AllocationEvent(double duration, intptr_t allocation_in_bytes);
+
+    // Time spent in the mutator during the end of the last garbage collection
+    // to the beginning of the next garbage collection.
+    double duration_;
+
+    // Memory allocated in the new space during the end of the last garbage
+    // collection to the beginning of the next garbage collection.
+    intptr_t allocation_in_bytes_;
+  };
+
   class Event {
    public:
     enum Type { SCAVENGER = 0, MARK_COMPACTOR = 1, START = 2 };
@@ -223,6 +239,8 @@ class GCTracer {
 
   typedef RingBuffer<Event, kRingBufferMaxSize> EventBuffer;
 
+  typedef RingBuffer<AllocationEvent, kRingBufferMaxSize> AllocationEventBuffer;
+
   explicit GCTracer(Heap* heap);
 
   // Start collecting data.
@@ -232,6 +250,9 @@ class GCTracer {
   // Stop collecting data and print results.
   void Stop();
 
+  // Log an allocation throughput event.
+  void AddNewSpaceAllocationTime(double duration, intptr_t allocation_in_bytes);
+
   // Log an incremental marking step.
   void AddIncrementalMarkingStep(double duration, intptr_t bytes);
 
@@ -297,6 +318,10 @@ class GCTracer {
   // Returns 0 if no events have been recorded.
   intptr_t MarkCompactSpeedInBytesPerMillisecond() const;
 
+  // Allocation throughput in the new space in bytes/millisecond.
+  // Returns 0 if no events have been recorded.
+  intptr_t NewSpaceAllocationThroughputInBytesPerMillisecond() const;
+
  private:
   // Print one detailed trace line in name=value format.
   // TODO(ernstm): Move to Heap.
@@ -331,6 +356,9 @@ class GCTracer {
   // RingBuffers for MARK_COMPACTOR events.
   EventBuffer mark_compactor_events_;
 
+  // RingBuffer for allocation events.
+  AllocationEventBuffer allocation_events_;
+
   // Cumulative number of incremental marking steps since creation of tracer.
   int cumulative_incremental_marking_steps_;
 
@@ -361,6 +389,10 @@ class GCTracer {
   // all sweeping operations performed on the main thread.
   double cumulative_sweeping_duration_;
 
+  // Holds the new space top pointer recorded at the end of the last garbage
+  // collection.
+  intptr_t new_space_top_after_gc_;
+
   DISALLOW_COPY_AND_ASSIGN(GCTracer);
 };
 }