Least Recently Used:

In Least Recently Used (LRU) algorithm is a Greedy algorithm where the page to be replaced is least recently used.

The idea is based on locality of reference, the least recently used page is not likely.

Advantages:

• Easy to choose page which has faulted and hasn’t been used for a long time.


• In this, we replace the page which is least recently used, thus free from Belady’s Anomaly.

Disadvantages:

• In LRU error detection is difficult as compared to other algorithms.


• It requires additional Data Structure to be implemented.


• LRU are very costly to operate.