--- old/src/hotspot/share/gc/z/zStat.cpp	2018-03-06 16:38:51.453375714 +0100
+++ new/src/hotspot/share/gc/z/zStat.cpp	2018-03-06 16:38:51.292368806 +0100
@@ -1012,7 +1012,7 @@
 uint64_t  ZStatCycle::_ncycles = 0;
 Ticks     ZStatCycle::_start_of_last;
 Ticks     ZStatCycle::_end_of_last;
-NumberSeq ZStatCycle::_duration(0.3 /* alpha */);
+NumberSeq ZStatCycle::_normalized_duration(0.3 /* alpha */);
 
 void ZStatCycle::at_start() {
   _start_of_last = Ticks::now();
@@ -1022,20 +1022,20 @@
   _end_of_last = Ticks::now();
   _ncycles++;
 
-  // Calculate cycle duration. The duration is normalized using the boost
-  // factor to avoid artificial deflation of the duration when boost mode
-  // is enabled.
+  // Calculate normalized cycle duration. The measured duration is
+  // normalized using the boost factor to avoid artificial deflation
+  // of the duration when boost mode is enabled.
   const double duration = TicksToTimeHelper::seconds(_end_of_last - _start_of_last);
   const double normalized_duration = duration * boost_factor;
-  _duration.add(normalized_duration);
+  _normalized_duration.add(normalized_duration);
 }
 
 uint64_t ZStatCycle::ncycles() {
   return _ncycles;
 }
 
-const AbsSeq& ZStatCycle::duration() {
-  return _duration;
+const AbsSeq& ZStatCycle::normalized_duration() {
+  return _normalized_duration;
 }
 
 double ZStatCycle::time_since_last() {