diff -r e4d90117c5de -r a7f16447085e src/hotspot/share/gc/z/zVirtualMemory.hpp
--- a/src/hotspot/share/gc/z/zVirtualMemory.hpp	Tue Sep 24 11:49:48 2019 +0200
+++ b/src/hotspot/share/gc/z/zVirtualMemory.hpp	Tue Sep 24 10:04:13 2019 +0000
@@ -50,11 +50,12 @@
   ZMemoryManager _manager;
   bool           _initialized;
 
-  bool reserve(uintptr_t start, size_t size);
+  bool reserve_platform(uintptr_t start, size_t size);
+  size_t reserve(uintptr_t start, size_t size);
   void nmt_reserve(uintptr_t start, size_t size);
 
 public:
-  ZVirtualMemoryManager();
+  ZVirtualMemoryManager(size_t max_capacity);
 
   bool is_initialized() const;