message: Add flag to control tf.data's autotune_buffer default setting.
diff: @@ -20,6 +20,9 @@ from __future__ import print_function
  from tensorflow.python.data.util import options
  from tensorflow.python.util.tf_export import tf_export
  +# Do not modify.
  +_ENABLE_AUTOTUNE_BUFFERS_BY_DEFAULT = False
  +
  @tf_export("data.experimental.MapVectorizationOptions")
  class MapVectorizationOptions(options.OptionsBase):
  @@ -214,7 +217,11 @@ class OptimizationOptions(options.OptionsBase):
  if self.map_vectorization is not None:
  result.update(self.map_vectorization._static_optimizations()) # pylint: disable=protected-access
  - if self.autotune is not False and self.autotune_buffers: # pylint: disable=g-bool-id-comparison
  + # The default setting for autotune_buffers is based on
  + # _ENABLE_AUTOTUNE_BUFFERS_BY_DEFAULT
  + autotune_buffers = self.autotune_buffers or (
  + self.autotune_buffers is None and _ENABLE_AUTOTUNE_BUFFERS_BY_DEFAULT)
  + if self.autotune is not False and autotune_buffers: # pylint: disable=g-bool-id-comparison
  result.add("inject_prefetch")
  return sorted(list(result))
  