--- a/hotspot/src/share/vm/classfile/javaClasses.cpp	Fri Jan 29 14:51:38 2010 -0800
+++ b/hotspot/src/share/vm/classfile/javaClasses.cpp	Mon Feb 01 17:29:01 2010 -0800
@@ -1121,10 +1121,23 @@
   }
 
   void flush() {
+    // The following appears to have been an optimization to save from
+    // doing a barrier for each individual store into the _methods array,
+    // but rather to do it for the entire array after the series of writes.
+    // That optimization seems to have been lost when compressed oops was
+    // implemented. However, the extra card-marks below was left in place,
+    // but is now redundant because the individual stores into the
+    // _methods array already execute the barrier code. CR 6918185 has
+    // been filed so the original code may be restored by deferring the
+    // barriers until after the entire sequence of stores, thus re-enabling
+    // the intent of the original optimization. In the meantime the redundant
+    // card mark below is now disabled.
     if (_dirty && _methods != NULL) {
+#if 0
       BarrierSet* bs = Universe::heap()->barrier_set();
       assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
       bs->write_ref_array((HeapWord*)_methods->base(), _methods->length());
+#endif
       _dirty = false;
     }
   }
@@ -1168,9 +1181,7 @@
       method = mhandle();
     }
 
-     _methods->obj_at_put(_index, method);
-    // bad for UseCompressedOops
-    // *_methods->obj_at_addr(_index) = method;
+    _methods->obj_at_put(_index, method);
     _bcis->ushort_at_put(_index, bci);
     _index++;
     _dirty = true;