--- old/src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp	2013-05-14 15:41:33.744528770 +0200
+++ new/src/share/vm/gc_implementation/g1/heapRegionRemSet.cpp	2013-05-14 15:41:33.384528777 +0200
@@ -242,11 +242,19 @@
     PerRegionTable* cur = _free_list;
     size_t res = 0;
     while (cur != NULL) {
-      res += sizeof(PerRegionTable);
+      res += cur->mem_size();
       cur = cur->next();
     }
     return res;
   }
+
+#ifndef PRODUCT
+  static void test() {
+    PerRegionTable* dummy = alloc(NULL);
+    free(dummy);
+    guarantee(dummy->mem_size() == fl_mem_size(), "fl_mem_size() does not return the correct element size");
+  }
+#endif
 };
 
 PerRegionTable* PerRegionTable::_free_list = NULL;
@@ -1147,6 +1155,10 @@
 }
 
 #ifndef PRODUCT
+void HeapRegionRemSet::test_prt() {
+  PerRegionTable::test();
+}
+
 void HeapRegionRemSet::test() {
   os::sleep(Thread::current(), (jlong)5000, false);
   G1CollectedHeap* g1h = G1CollectedHeap::heap();