--- old/src/share/vm/gc/g1/g1ConcurrentMark.hpp	2016-09-14 14:48:25.867549801 +0200
+++ new/src/share/vm/gc/g1/g1ConcurrentMark.hpp	2016-09-14 14:48:25.728545499 +0200
@@ -181,7 +181,8 @@
   OopChunk* volatile _free_list;  // Linked list of free chunks that can be allocated by users.
   char _pad1[DEFAULT_CACHE_LINE_SIZE - sizeof(OopChunk*)];
   OopChunk* volatile _chunk_list; // List of chunks currently containing data.
-  char _pad2[DEFAULT_CACHE_LINE_SIZE - sizeof(OopChunk*)];
+  volatile size_t _chunks_in_chunk_list;
+  char _pad2[DEFAULT_CACHE_LINE_SIZE - sizeof(OopChunk*) - sizeof(size_t)];
  
   volatile size_t _hwm;          // High water mark within the reserved space.
   char _pad4[DEFAULT_CACHE_LINE_SIZE - sizeof(size_t)];
@@ -190,8 +191,6 @@
   // NULL if out of memory.
   OopChunk* allocate_new_chunk();
 
-  volatile size_t _chunks_in_chunk_list;
-
   volatile bool _out_of_memory;
 
   // Atomically add the given chunk to the list.