“…For instance, a dynamic website may include a half dozen cache mechanisms: at the database layer [11,25], data interface layer [11], scripting layer, virtual file system, and the network proxy layer [14]. Several cache systems for dynamic websites attempt to map underlying queries to cache objects for intelligent invalidation [13,20,25]. The web application as a whole may also include several programmatic caches to cache repeated function results, web objects, and templates [3].…”