title: Package DBMS_PARALLEL_EXECUTE - how to stop(kill) executing task
body: <p>We are using DBMS_PARALLEL_EXECUTE in Oracle 11g R2 as following</p>
  
  <p>scheduled job run a procedure which creates and runs parallel task using package DBMS_PARALLEL_EXECUTE. Sometime scheduled job hangs and is needed to be restarted. And my question is how to properly kill executing parallel task?
  Using DBMS_PARALLEL_EXECUTE.DROP_TASK or DBMS_PARALLEL_EXECUTE.STOP_TASK procedures do not help - I can see sessions of task processes (it creates the same amount of new processes as parameter parallel_level of DBMS_PARALLEL_EXECUTE.RUN_TASK). The same with killing scheduled job (dbms_job.remove) and killing job session - task sessions still available.</p>