1. A method of selecting a victim cache line from among a plurality of cache lines in a congruence class of a cache memory, wherein each of the cache lines belongs to one of multiple classes including at least a first class and a second class, said method comprising: if the congruence class contains a cache line belonging to the second class, preferentially selecting as a victim cache line a cache line of the congruence class belonging to the second class, wherein the selecting includes selecting the cache line belonging to the second class based upon access order; if the congruence class contains no cache line belonging to the second class, selecting as the victim cache line a cache line belonging to the first class based upon access order; and evicting the selected victim cache line.