D_LOCK
D_LOCK(("*** NodeGroup::lock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeGroup::lock() ACQUIRED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeGroup::unlock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeGroup::unlock() RELEASED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeManager::lock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeManager::lock() ACQUIRED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeManager::unlock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeManager::unlock() RELEASED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeRef::lock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeRef::lock() ACQUIRED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeRef::unlock(): %ld\n", find_thread(0)));
D_LOCK(("*** NodeRef::unlock() RELEASED: %ld\n", find_thread(0)));
D_LOCK(("*** NodeRef::unlock() RELEASED: %ld\n", find_thread(0)));