#524 mod_pep: User JIDs are cached permanently in recipients table
mod_pep has a cache of nodes that JIDs are subscribed to. They are not removed from this table when they go offline.
While many servers have a finite number of user accounts, this behaviour can cause unbounded gradual memory growth on domains with lots of unique JIDs, e.g. those using anonymous authentication.
A potential simple fix would be to remove a JID from the table on resource-unbind.