public void shutdown() {
    if (executor != null) {
      executor.shutdownNow();
    }
    if (taskReporter != null) {
      taskReporter.shutdown();
    }
    if (umbilical != null) {
      // TODO: Can this be moved out of the main callback path
      RPC.stopProxy(umbilical);
    }
  }
Inform the AM that this task has been killed.
llap-server/src/java/org/apache/hadoop/hive/llap/daemon/impl/TaskRunnerCallable.java