---
upgrade:
  - The get_metrics API has been replaced by
    populate_metrics in nova.compute.monitors.base
    module. This change is introduced to allow each
    monitor plugin to have the flexibility of setting
    it's own metric value types. The in-tree metrics
    plugins are modified as a part of this change.
    However, the out-of-tree plugins would have to
    adapt to the new API in order to work with nova.