void addTaskAttempt(TezTaskAttemptID attemptId, boolean isGuaranteed) {
      Boolean oldVal = tasks.putIfAbsent(attemptId, isGuaranteed);
      if (oldVal != null) {
        throw new RuntimeException(attemptId + " was already registered");
      }
    }
Responsible for communicating with various AMs.
llap-server/src/java/org/apache/hadoop/hive/llap/daemon/impl/AMReporter.java