In operating systems, whenever a new page is referred and not present in memory, page fault occurs and Operating System replaces one of the existing pages with newly needed page. Different page replacement algorithms suggest different ways to decide which page to replace. The target for all algorithms is to reduce number of page faults. In this algorithm, OS replaces the page that will not be used for the longest period of time in future.  

 

Input number of frames=4 

Reference string= 7,0,1,2,0,3,0,4,2,3,0,3,2,1,2,0,1,7,0,1.

 

(A) Find out number of misses 

(B) Find out number of hits 

(C) Find out number of page faults