Add aggregated memory histograms.

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/v8.h"
 
 #include "src/base/platform/platform.h"
 #include "src/counters.h"
 #include "src/isolate.h"
 #include "src/log-inl.h"
@@ skipping 61 matching lines @@
 #define AHT(name, caption) \
   name##_ = AggregatableHistogramTimer(#caption, 0, 10000000, 50, isolate);
     AGGREGATABLE_HISTOGRAM_TIMER_LIST(AHT)
 #undef AHT
 
 #define HP(name, caption) \
     name##_ = Histogram(#caption, 0, 101, 100, isolate);
     HISTOGRAM_PERCENTAGE_LIST(HP)
 #undef HP
 
+
+// Exponential histogram assigns bucket limits to points
+// p[1], p[2], ... p[n] such that p[i+1] / p[i] = constant.
+// The constant factor is equal to the n-th root of (high / low),
+// where the n is the number of buckets, the low is the lower limit,
+// the high is the upper limit.
+// For n = 50, low = 1000, high = 500000: the factor = 1.13.
 #define HM(name, caption) \
     name##_ = Histogram(#caption, 1000, 500000, 50, isolate);
+  HISTOGRAM_LEGACY_MEMORY_LIST(HM)
+#undef HM
+// For n = 100, low = 4000, high = 2000000: the factor = 1.06.
+#define HM(name, caption) \
+  name##_ = Histogram(#caption, 4000, 2000000, 100, isolate);
+  HISTOGRAM_MEMORY_LIST(HM)
+#undef HM
+
+#define HM(name, caption) \
+  aggregated_##name##_ = AggregatedMemoryHistogram<Histogram>(&name##_);
     HISTOGRAM_MEMORY_LIST(HM)
 #undef HM
 
 #define SC(name, caption) \
     name##_ = StatsCounter(isolate, "c:" #caption);
 
     STATS_COUNTER_LIST_1(SC)
     STATS_COUNTER_LIST_2(SC)
 #undef SC
 
@@ skipping 72 matching lines @@
 
 #define AHT(name, caption) name##_.Reset();
     AGGREGATABLE_HISTOGRAM_TIMER_LIST(AHT)
 #undef AHT
 
 #define HP(name, caption) name##_.Reset();
     HISTOGRAM_PERCENTAGE_LIST(HP)
 #undef HP
 
 #define HM(name, caption) name##_.Reset();
-    HISTOGRAM_MEMORY_LIST(HM)
+    HISTOGRAM_LEGACY_MEMORY_LIST(HM)
 #undef HM
 }
 
 } }  // namespace v8::internal