1
1) (60 pts – 15 pts each) For the reference string shown below, determine the number of page faults
that occur for (a) FIFO replacement algorithm, (b) LRU replacement algorithm (c) Optimal
replacement algorithm. Do parts (a)-(c) for allocations of (1) three page frame allocation and (2)
four page frame allocation. Does this reference string suffer from Belady’s anomaly for the FIFO
algorithm?
Reference string: 1, 2, 3, 4, 5, 3, 4, 1, 6, 7, 8, 7, 8, 9, 7, 8, 9, 5, 4, 5, 4, 2
Three-frame allocation
FIFO
Ref. String
1
2
3
4
5
3
4
1
6
7
8
7
8
9
7
8
9
5
4
5
4
2
frame
1
1
1
1
2
3
3
3
4
5
1
6
6
6
7
7
7
7
8
9
9
9
5
2
2
2
3
4
4
4
5
1
6
7
7
7
8
8
8
8
9
5
5
5
4
3
3
4
5
5
5
1
6
7
8
8
8
9
9
9
9
5
4
4
4
2
total faults
page fault
Y
Y
Y
Y
Y
N
N
Y
Y
Y
Y
N
N
Y
N
N
N
Y
Y
N
N
Y
13
LRU
Ref. String
1
2
3
4
5
3
4
1
6
7
8
7
8
9
7
8
9
5
4
5
4
2
frame
1
1
1
1
2
3
4
5
3
4
1
6
6
6
7
8
9
7
8
9
9
9
5
2
2
2
3
4
5
3
4
1
6
7
8
7
8
9
7
8
9
5
4
5
4
3
3
4
5
3
4
1
6
7
8
7
8
9
7
8
9
5
4
5
4
2
total faults
page fault
Y
Y
Y
Y
Y
N
N
Y
Y
Y
Y
N
N
Y
N
N
N
Y
Y
N
N
Y
13
Optimal
Ref. String
1
2
3
4
5
3
4
1
6
7
8
7
8
9
7
8
9
5
4
5
4
2
frame
1
1
2
2
1
5
3
3
1
6
4
5
5
5
9
7
7
7
8
9
9
9
5
2
1
1
4
4
4
4
4
4
5
8
8
8
8
9
8
8
9
4
5
5
4
3
3
3
3
5
5
5
5
7
7
7
7
7
8
9
9
5
5
4
4
2
total faults
page fault
Y
Y
Y
Y
Y
N
N
Y
Y
Y
Y
N
N
Y
N
N
N
Y
Y
N
N
Y
13
COP 4600 – Introduction To Operating Systems – Summer 2009
Homework #3 – 100 points
KEY
