Control starts at block 702 in which the cache management application 116 adds the track with minimum retention time to the MRU end of the LRU list 118 for any tier of cache. Control proceeds to block 704 in which the cache management application 116 places a timestamp to indicate when the track was added to the MRU end of the LRU list 118. The timestamp is kept in association with the track that is added to the LRU list 118

From block 704 control proceeds to block 706 in which the cache management application 116 stores the minimum retention time of the track in association with the track that is added to the LRU list 118. The cache management application 116 then increments (i.e., adds the number 1) to the number of minimum retention time tracks (as shown via block 708).

Therefore, FIG. 7 shows certain embodiments in which tracks are added to the LRU list 118 of any tier of cache with indication of the minimum retention time and a timestamp that records the time at which the track was added to the LRU list. The number of tracks with minimum retention time is updated when a track with a minimum retention time is added to the LRU list 118. It should be noted that the corresponding LRU list 118 is updated each time a track is added to a tier of the cache 104.