Consider a main memory with 3 page frames. The following sequence of page…
2021
Consider a main memory with 3 page frames. The following sequence of page references is: 3, 4, 2, 3, 9, 1, 6, 3, 4, 9. What is the number of page faults using the FIFO page replacement algorithm?
- A.
9
- B.
10
- C.
8
- D.
7
Attempted by 126 students.
Show answer & explanation
Correct answer: A
Page Frames: 3
Reference String: 3, 4, 2, 3, 9, 1, 6, 3, 4, 9
Algorithm: FIFO (The page that entered the frame first is the first to be replaced).
Step-by-Step Execution
Reference | Frame 1 | Frame 2 | Frame 3 | Result |
3 | 3 | Fault (1) | ||
4 | 3 | 4 | Fault (2) | |
2 | 3 | 4 | 2 | Fault (3) |
3 | 3 | 4 | 2 | Hit |
9 | 9 | 4 | 2 | Fault (4) - 3 was oldest |
1 | 9 | 1 | 2 | Fault (5) - 4 was oldest |
6 | 9 | 1 | 6 | Fault (6) - 2 was oldest |
3 | 3 | 1 | 6 | Fault (7) - 9 was oldest |
4 | 3 | 4 | 6 | Fault (8) - 1 was oldest |
9 | 3 | 4 | 9 | Fault (9) - 6 was oldest |
Total Page Faults: 9