* Fixed an issue where read-only operations that used local worker processes (i.e. restore) were creating write locks that could interfere with parallel archive-push. (Reported by Jens Wilke.)
* Simplify locking scheme. Now, only the master process will hold write locks (archive-push, backup) and not all the local and remote worker processes as before.
The stanza-upgrade command provides a mechanism for upgrading a stanza after upgrading to a new major version of PostgreSQL.
Contributed by Cynthia Shang.