GATE 2022 CS – Question 64
Consider a demand paging system with four page frames (initially empty) and LRU page replacement policy. For the following page reference string
7, 2, 7, 3, 2, 5, 3, 4, 6, 7, 7, 1, 5, 6, 1
the page fault rate, defined as the ratio of number of page faults to the number of memory accesses (rounded off to one decimal place) is _________.
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: 0.6
Explanation
Simulating LRU with 4 frames, the faults occur on 7, 2, 3, 5, 4, 6, 7, 1 and 5, for 9 faults out of 15 references. The rate is 9/15 = 0.6.