Patent attributes
A method for demoting data elements from a cache is disclosed. The method maintains a heterogeneous cache comprising a higher performance portion and a lower performance portion. The method maintains, within the lower performance portion, a ghost cache containing statistics for data elements that are currently contained in the heterogeneous cache, and data elements that have been demoted from the heterogeneous cache within a specified time interval. The method maintains, for the ghost cache, multiple LRU lists that designate an order in which data elements are demoted from the lower performance portion. The method utilizes the statistics to determine in which LRU lists the data elements are referenced. A corresponding system and computer program product are also disclosed.
