First-In-First-Out:

This is one of the simplest page replacement algorithm.

In this algorithm, OS maintains a queue that keeps track of all the pages in the memory, where the oldest page is at front and the most recent one at back.

When the page is needed to be replaced, this algorithm swaps out the page that is at front as it has been there for the longest time.

Advantages:

• It is simple, easy to understand and implement.


• It has easy and fast execution

Disadvantages:

• The process effectiveness is very low.


• Every frame needs to be taken account of.


• With increase in no. of pages, no of page-faults also increases.