---
features:
  - |
    Bump up the max_files to 32768 and max_processes to 131072.
    when nova used ceph as backend, the default limit 1024 is not enough.
    each connection from rbd image to osd needs 1 fd and 2 threads. if we
    have 200 osds, we need 200 fds and 400 threads for 1 image.