Sessions, wicket file store and deleting old pagemap session data

["Brown, Berlin [GCG-PFS]" <Be...@Primerica.com>]

If I look at my wicket file store (wicket.wicket-filestore).  I notice
that a lot of older web sessions do not get deleted.  My thinking is
that the default second level cache unbind method is not getting called.
 
I think if I explicitly call the "invalidate" method or have a html link
to invalidate the session, that seems to delete the cached data for that
session.  But, if I let the session expire after the default 60 minutes.
Will the session invalidate method get called?
 
Also, I guess if the server is restarted, does all of that session
information in memory get destroyed, so wicket never deletes the cached
information associated with older sessions.
 
Berlin Brown