Operating Systems - Old Questions

2.  What is page fault? Consider the following page reference string; 3, 3, 5, 4, 7, 1, 5, 5, 1, 4, 3, 7, 6, 3, 4, 1. How many page faults would occur for each of the following page replacement algorithms assuming 4 page frames?

        a.) LRU page replacement

        b.) FIFO page replacement

        c.) Optimal page replacement

        d.) Clock replacement