---
features:
  - |
    The port hints extension (``port-hints``) introduces the ``hints``
    port attribute. Hints are backend specific pieces of information,
    mainly to allow backend specific performance tuning. In itself this
    extension defines no particular hint, and therefore no valid values
    of the ``hints`` attribute. It just serves as the base for other
    extensions introducing concrete hints and signals the presence of
    the ``hints`` port attribute to the API user. By default policy,
    use of the ``hints`` attribute is restricted to admininstrative users.
