---
fixes:
  - |
    [`bug 1819036 <https://bugs.launchpad.net/keystone/+bug/1819036>`_]
    Middleware that processes requests in front of keystone now caches tokens
    per request, eliminating unnecessary round trips to validate tokens on
    every request. This change doesn't require the usage of any configuration
    options to take effect. The fix for this bug improved performance ~20% during
    testing and impacts most of keystone's API.