We need to add unit tests to verify SLRP correctness when the set of known profiles are shrunk by the disk profile adaptor. Here lists a couple scenarios worth testing:
1. `CREATE_VOLUME` should succeed if it is submitted before the profile becomes stale.
2. `CREATE_VOLUME` should be dropped if it is submitted after the profile becomes stale.
3. `DESTROY_VOLUME` should free spaces for a stale profile.