---
features:
  - >
    Support for queue based communication between alarm evaluator service and
    alarm notifier services was added. Original implementation involved using
    RPC but there is significant overhead involved with using RPC. Work queues
    provided required functionality with better performance.
upgrade:
  - >
    Queue based communication is the new default IPC protocol. RPC can still
    be used by choosing rpc as ipc_protocol option. Only one protocol can be
    run at any given time.
deprecations:
  - >
    Because queues provide the equivalent functionality. RPC support is
    deprecated and will be removed after Mitaka.