message: Add an option in multi_worker_test_base.create_in_process_cluster to choose different rpc_layer.
diff: @@ -140,7 +140,8 @@ def _create_cluster(num_workers,
  def create_in_process_cluster(num_workers,
  num_ps,
  has_chief=False,
  - has_eval=False):
  + has_eval=False,
  + rpc_layer='grpc'):
  """Create an in-process cluster that consists of only standard server."""
  # Leave some memory for cuda runtime.
  gpu_mem_frac = 0.7 / (num_workers + int(has_chief) + int(has_eval))
  @@ -180,7 +181,7 @@ def create_in_process_cluster(num_workers,
  worker_config=worker_config,
  ps_config=ps_config,
  eval_config=eval_config,
  - protocol='grpc')
  + protocol=rpc_layer)
  def create_cluster_spec(test_obj,
  