diff -r 8a3599d60996 -r 5d20359dd938 src/hotspot/share/memory/metaspace.hpp
--- a/src/hotspot/share/memory/metaspace.hpp	Tue Sep 26 14:05:27 2017 +0200
+++ b/src/hotspot/share/memory/metaspace.hpp	Thu Sep 28 09:56:54 2017 -0400
@@ -273,7 +273,7 @@
   // Running sum of space in all Metachunks that
   // are being used for metadata. One for each
   // type of Metadata.
-  static size_t _used_words[Metaspace:: MetadataTypeCount];
+  static volatile size_t _used_words[Metaspace:: MetadataTypeCount];
 
  public:
   // Decrement and increment _allocated_capacity_words