title: Expiration of NHibernate syscache
body: <p>How works expiration of NHibernate's syscache?</p>
  
  <p>If I set expiration to 10 minutes, and each minute I add an entity, when the first 10 minutes (after application start) end, are all 10 entities deleted, or only the first one?</p>
  
  <p>Are all data removed from cache altogether, or is there a timestamp for each entity?</p>