One common replacement policy is least-recently used (LRU). In LRU replacement, the cache ranks each of the lines in a set according to how recently they have been accessed and evict the least-recently used line from a set when an eviction is necessary. This is based on the observation that lines that have not been referenced in the recent past are unlikely to be referenced in the near future. Another policy that has been studied is random replacement, in which a randomly selected line from the appropriate set is evicted to make room for incoming data.