Collect array buffer allocation sizes for UMA in megabytes.

src/counters.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/counters.h"
 
 #include <iomanip>
 
 #include "src/base/platform/platform.h"
 #include "src/builtins/builtins-definitions.h"
@@ skipping 63 matching lines @@
       HISTOGRAM_RANGE_LIST(HR)
 #undef HR
   };
   for (const auto& histogram : kHistograms) {
     this->*histogram.member =
         Histogram(histogram.caption, histogram.min, histogram.max,
                   histogram.num_buckets, isolate);
   }
 
   static const struct {
+    MegabyteHistogram Counters::*member;
+    const char* caption;

[Mircea Trofin, 2017/04/03 17:26:20]

could we initialize the members in-place? (caption = nullptr.. etc)

[kschimpf, 2017/04/03 17:33:41]

Explicit initialization is done in the entries using macro
MEGABYTE_HISTOGRAM_RANGE_LIST.

+    int min;
+    int max;
+    int num_buckets;
+  } kMegabyteHistograms[] = {
+#define HR(name, caption, min, max, num_buckets) \
+  {&Counters::name##_, #caption, min, max, num_buckets},
+      MEGABYTE_HISTOGRAM_RANGE_LIST(HR)
+#undef HR
+  };
+  for (const auto& histogram : kMegabyteHistograms) {
+    this->*histogram.member =
+        MegabyteHistogram(histogram.caption, histogram.min, histogram.max,
+                          histogram.num_buckets, isolate);
+  }
+
+  static const struct {
     HistogramTimer Counters::*member;
     const char* caption;
     int max;
     HistogramTimer::Resolution res;
   } kHistogramTimers[] = {
 #define HT(name, caption, max, res) \
   {&Counters::name##_, #caption, max, HistogramTimer::res},
       HISTOGRAM_TIMER_LIST(HT)
 #undef HT
   };
@@ skipping 137 matching lines @@
   CODE_AGE_LIST_COMPLETE(SC)
 #undef SC
 }
 
 
 void Counters::ResetHistograms() {
 #define HR(name, caption, min, max, num_buckets) name##_.Reset();
   HISTOGRAM_RANGE_LIST(HR)
 #undef HR
 
+#define HR(name, caption, min, max, num_buckets) name##_.Reset();
+  MEGABYTE_HISTOGRAM_RANGE_LIST(HR)
+#undef HR
+
 #define HT(name, caption, max, res) name##_.Reset();
     HISTOGRAM_TIMER_LIST(HT)
 #undef HT
 
 #define AHT(name, caption) name##_.Reset();
     AGGREGATABLE_HISTOGRAM_TIMER_LIST(AHT)
 #undef AHT
 
 #define HP(name, caption) name##_.Reset();
     HISTOGRAM_PERCENTAGE_LIST(HP)
@@ skipping 238 matching lines @@
        RuntimeCallStats::counters) {
     RuntimeCallCounter* counter = &(this->*counter_id);
     if (counter->count() > 0) counter->Dump(value);
   }
 
   in_use_ = false;
 }
 
 }  // namespace internal
 }  // namespace v8