--- a/src/share/vm/memory/genMarkSweep.cpp	Tue Sep 28 09:51:37 2010 -0700
+++ b/src/share/vm/memory/genMarkSweep.cpp	Tue Sep 28 15:56:15 2010 -0700
@@ -161,17 +161,6 @@
 
   _preserved_marks = (PreservedMark*)scratch;
   _preserved_count = 0;
-  _preserved_mark_stack = NULL;
-  _preserved_oop_stack = NULL;
-
-  _marking_stack       = new (ResourceObj::C_HEAP) GrowableArray<oop>(4000, true);
-  _objarray_stack      = new (ResourceObj::C_HEAP) GrowableArray<ObjArrayTask>(50, true);
-
-  int size = SystemDictionary::number_of_classes() * 2;
-  _revisit_klass_stack = new (ResourceObj::C_HEAP) GrowableArray<Klass*>(size, true);
-  // (#klass/k)^2 for k ~ 10 appears to be a better fit, but this will have to do for
-  // now until we have had a chance to investigate a more optimal setting.
-  _revisit_mdo_stack   = new (ResourceObj::C_HEAP) GrowableArray<DataLayout*>(2*size, true);
 
 #ifdef VALIDATE_MARK_SWEEP
   if (ValidateMarkSweep) {
@@ -206,17 +195,12 @@
     gch->release_scratch();
   }
 
-  if (_preserved_oop_stack) {
-    delete _preserved_mark_stack;
-    _preserved_mark_stack = NULL;
-    delete _preserved_oop_stack;
-    _preserved_oop_stack = NULL;
-  }
-
-  delete _marking_stack;
-  delete _objarray_stack;
-  delete _revisit_klass_stack;
-  delete _revisit_mdo_stack;
+  _preserved_mark_stack.clear(true);
+  _preserved_oop_stack.clear(true);
+  _marking_stack.clear();
+  _objarray_stack.clear(true);
+  _revisit_klass_stack.clear(true);
+  _revisit_mdo_stack.clear(true);
 
 #ifdef VALIDATE_MARK_SWEEP
   if (ValidateMarkSweep) {
@@ -274,17 +258,17 @@
 
   // Update subklass/sibling/implementor links of live klasses
   follow_weak_klass_links();
-  assert(_marking_stack->is_empty(), "just drained");
+  assert(_marking_stack.is_empty(), "just drained");
 
   // Visit memoized MDO's and clear any unmarked weak refs
   follow_mdo_weak_refs();
-  assert(_marking_stack->is_empty(), "just drained");
+  assert(_marking_stack.is_empty(), "just drained");
 
   // Visit symbol and interned string tables and delete unmarked oops
   SymbolTable::unlink(&is_alive);
   StringTable::unlink(&is_alive);
 
-  assert(_marking_stack->is_empty(), "stack should be empty by now");
+  assert(_marking_stack.is_empty(), "stack should be empty by now");
 }