private void waitOnLock() throws InterruptedException {
      if (isShutdown.get()) return;
      nextSanityCheck = System.nanoTime() + SANITY_CHECK_TIMEOUT_MS * 1000000L;
      lock.wait(SANITY_CHECK_TIMEOUT_MS);
    }
Worker that takes tasks from wait queue and schedule it for execution.
llap-server/src/java/org/apache/hadoop/hive/llap/daemon/impl/TaskExecutorService.java