--- old/src/share/vm/services/memTracker.cpp	Fri Jul 13 08:04:54 2012
+++ new/src/share/vm/services/memTracker.cpp	Fri Jul 13 08:04:52 2012
@@ -361,6 +361,10 @@
       // VM state, so it can stop at safepoint. JavaThread running in VM state does not
       // need lock to write records.
       if (thread->is_Java_thread() && ((JavaThread*)thread)->is_safepoint_visible()) {
+        assert(!(SafepointSynchronize::is_at_safepoint() && 
+          ((JavaThread*)thread)->thread_state() == _thread_blocked),
+           "_thread_blocked allocate/deallocation memory at safepoint");
+
         if (((JavaThread*)thread)->thread_state() == _thread_in_native) {
           ThreadInVMfromNative trans((JavaThread*)thread);
           create_record_in_recorder(addr, flags, size, pc, thread);
@@ -486,8 +490,6 @@
 
   // now, it is the time to shut whole things off
   if (_state == NMT_final_shutdown) {
-    _tracking_level = NMT_off;
-
     // walk all JavaThreads to delete all recorders
     SyncThreadRecorderClosure stc;
     Threads::threads_do(&stc);
@@ -499,8 +501,16 @@
         _global_recorder = NULL;
       }
     }
-
-    _state = NMT_shutdown;
+    MemRecorder* pending_recorders = get_pending_recorders();
+    if (pending_recorders != NULL) {
+      delete pending_recorders;
+    }
+    // wait until MemRecorder instance drops to zero to
+    // completely shutdown NMT
+    if (MemRecorder::_instance_count == 0) {
+      _state = NMT_shutdown;
+      _tracking_level = NMT_off;
+    }
   }
 }