Oracle DBMS UTILITY CPU Time

variable t1 NUMBER
variable cpu1 NUMBER


BEGIN
  :t1 := dbms_utility.get_time;
  :cpu1 := dbms_utility.get_cpu_time;
  dbms_application_info.set_client_info(0);
END;
/

-- Sample CPU Only
Begin
FOR i IN 1..1000000 LOOP
  NULL;
END LOOP;
END;
/

-- Sample CPU and I/O
Begin
FOR i IN (SELECT * FROM all_objects) LOOP
  NULL;
END LOOP;
END;
/

SELECT 
  dbms_utility.get_time - :t1 AS time_hsecs, 
  dbms_utility.get_cpu_time - :cpu1 AS cpu_hsecs,
  userenv('client_info') as calls
FROM dual;