Status StartAndCollectCostGraph(Session* sess,
                                  const RunOptions& run_options = RunOptions());

  /// Starts the queue runner with the given session, and wait for up to the
  /// specified time (in milliseconds) for the queues to start to fill up.
  Status Start(Session* sess, int wait_for_ms);
  Status StartAndCollectCostGraph(Session* session, int wait_for_ms,

  // Cannot run Stop() here because the session might already be closed or
  // destroyed.
  Join().IgnoreError();
}

Status QueueRunner::Start(Session* sess) { return Start(sess, 0); }

Status QueueRunner::StartAndCollectCostGraph(Session* sess,
                                             const RunOptions& run_options) {
  SetRunArgumentsAndCostGraph(run_options);
  return Start(sess, 0);
}

      BuildQueueRunnerDef(kQueueName, {kEnqueueOp0}, kCloseOp0, kCancelOp0, {});
  std::unique_ptr<QueueRunner> qr;
  TF_EXPECT_OK(QueueRunner::New(queue_runner_def, &qr));
  RunOptions run_options;
  TF_CHECK_OK(qr->StartAndCollectCostGraph(session.get(), run_options));

  // Make sure there was at least one element enqueued in q0: this prevents a
  // race condition where we close the queue before it was populated.
  std::vector<Tensor> dq0;