page replacement algorithms some of the better-known page replacement policies include the following (see figure )first-infirst-out (fifo)evict the page that has been in the cache the longestthat isthe page that was transferred to the cache furthest in the past least recently used (lru)evict the page whose last request occurred furthest in the past in additionwe can consider simple and purely random strategyrandomchoose page at random to evict from the cache new block old block (chosen at randomnew block old block (present longestrandom policyfifo policyinsert time : am : am : am : am new block : am : am : am old block (least recently usedlru policylast used : am : am : am : am : am : am : am figure the randomfifoand lru page replacement policies the random strategy is one of the easiest policies to implementfor it only requires random or pseudo-random number generator the overhead involved in implementing this policy is an ( additional amount of work per page replacement moreoverthere is no additional overhead for each page requestother than to determine whether page request is in the cache or not stillthis policy makes no attempt to take advantage of any temporal locality exhibited by user' browsing