Add histograms for total allocated/live heap size, as well as allocated size and percentage of tota…

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 48cf266826dd53b6dae18a328a1959c206c12eb7..2ec740c08c8ab1ae25e621993419599a34c2ee7f 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -453,6 +453,22 @@ void Heap::GarbageCollectionEpilogue() {
   if (CommittedMemory() > 0) {
     isolate_->counters()->external_fragmentation_total()->AddSample(
         static_cast<int>(100 - (SizeOfObjects() * 100.0) / CommittedMemory()));
+
+    isolate_->counters()->heap_fraction_map_space()->AddSample(
+        static_cast<int>(
+            (map_space()->CommittedMemory() * 100.0) / CommittedMemory()));
+    isolate_->counters()->heap_fraction_cell_space()->AddSample(
+        static_cast<int>(
+            (cell_space()->CommittedMemory() * 100.0) / CommittedMemory()));
+
+    isolate_->counters()->heap_sample_total_committed()->AddSample(
+        CommittedMemory() / KB);
+    isolate_->counters()->heap_sample_total_used()->AddSample(
+        SizeOfObjects() / KB);
+    isolate_->counters()->heap_sample_map_space_committed()->AddSample(
+        map_space()->CommittedMemory() / KB);
+    isolate_->counters()->heap_sample_cell_space_committed()->AddSample(
+        cell_space()->CommittedMemory() / KB);
   }
 
 #define UPDATE_COUNTERS_FOR_SPACE(space)                                       \