Patent ID: 8271750
Filing Date: 2012-09-18
Classification: G06F

Abstract:
1. Apparatus for processing data comprising: a data store having a plurality of storage locations; an entry profile store of profile data for candidate entries to be stored in storage locations of said data store, said entry profile store serving to store profile data for more candidate entries than there are storage locations within said data store; and an entry replacer, configured to compare, in response to a miss in said data store, said profile data stored in said entry profile store for at least a candidate entry and an existing entry, the comparison being triggered by a miss in said data store, and to control whether said candidate entry replaces said existing entry within a storage location of said data store in dependence on the comparison; wherein said profile data includes performance gain data indicative of performance gains associated with use of respective candidate entries stored within said data store and said entry replacer preferentially stores candidate entries with a high associated performance gain when stored within said data store; further comprising a profile data updater to update said performance gain data in dependence upon cycle counts associated with actual use of a candidate entry when not stored within said data store, and to update said performance gain data in dependence upon cycle counts associated with actual use of a candidate entry when stored within said data store, wherein said profile data includes confidence data indicative of probabilities of predictions made in dependence upon storing respective candidate entries within said data store being correct and said entry replacer is configured to preferentially store candidate entries with a high probability of resulting in a correct prediction when stored within said data store.