--- old/src/share/vm/gc/g1/g1RemSet.cpp	2017-07-03 15:54:22.937018578 +0200
+++ new/src/share/vm/gc/g1/g1RemSet.cpp	2017-07-03 15:54:22.806014542 +0200
@@ -724,7 +724,7 @@
       sdcq->enqueue(card_ptr);
     }
   } else {
-    _num_conc_refined_cards++;
+    _num_conc_refined_cards++; // Unsynchronized update, only used for logging.
   }
 }