message: Added comment/TODO concerning memory use of extract_images_patches.
diff: @@ -580,6 +580,9 @@ class ConvDiagonalFactor(DiagonalFactor):
  # the target entry of _outputs_grads changes with idx.)
  with _maybe_colocate_with(inputs, self._colocate_cov_ops_with_inputs):
  filter_height, filter_width, _, _ = self._filter_shape
  +
  + # TODO(b/64144716): there is potential here for a big savings in terms of
  + # memory use.
  patches = array_ops.extract_image_patches(
  inputs,
  ksizes=[1, filter_height, filter_width, 1],
  @@ -739,6 +742,9 @@ class ConvInputKroneckerFactor(InverseProvidingFactor):
  # TODO(jamesmartens): factor this patches stuff out into a utility function
  with _maybe_colocate_with(self._inputs, self._colocate_cov_ops_with_inputs):
  filter_height, filter_width, in_channels, _ = self._filter_shape
  +
  + # TODO(b/64144716): there is potential here for a big savings in terms of
  + # memory use.
  patches = array_ops.extract_image_patches(
  self._inputs,
  ksizes=[1, filter_height, filter_width, 1],
  