--- old/src/hotspot/share/gc/z/zStat.hpp	2018-03-06 13:23:13.757164224 +0100
+++ new/src/hotspot/share/gc/z/zStat.hpp	2018-03-06 13:23:13.588156967 +0100
@@ -218,18 +218,9 @@
 };
 
 class ZStatPhaseCycle : public ZStatPhase {
-private:
-  static uint64_t  _ncycles;
-  static Ticks     _end_of_last;
-  static NumberSeq _duration;
-
 public:
   ZStatPhaseCycle(const char* name);
 
-  static uint64_t ncycles();
-  static const AbsSeq& duration();
-  static double time_since_last();
-
   virtual void register_start(const Ticks& start) const;
   virtual void register_end(const Ticks& start, const Ticks& end) const;
 };
@@ -345,6 +336,25 @@
 };
 
 //
+// Stat cycle
+//
+class ZStatCycle : public AllStatic {
+private:
+  static uint64_t  _ncycles;
+  static Ticks     _start_of_last;
+  static Ticks     _end_of_last;
+  static NumberSeq _duration;
+
+public:
+  static void at_start();
+  static void at_end(double boost_factor);
+
+  static uint64_t ncycles();
+  static const AbsSeq& duration();
+  static double time_since_last();
+};
+
+//
 // Stat load
 //
 class ZStatLoad : public AllStatic {