Discussed different page replacement algorithms and their hardware implementation. Explained the cause of thrashing.

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7 7
0
7
0
1
2
0
1
2
3
1
2
3
0
4
3
0
4
2
0
4
2
3
0
2
3
0
1
3
0
1
2
7
1
2
7
0
2
7
0
1
7 0 1 2 3 0 4 2 3 0 3 2 1 2 0 1 7 0 1
0
Number of page fault = 15

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7 7
0
7
0
1
7
0
1
2
3
0
1
2
3
4
1
2
3
4
0
2
3
4
0
1
2
4
0
1
2
7
0
1
7 0 1 2 3 0 4 2 3 0 3 2 1 2 0 1 7 0 1
0
Number of page fault = 10
Page fault decreases with the increase of frame size

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For some page-replacement algorithms e.g., FIFO, page fault increases with the increase
in frame size
This weird scenario is known as Belady’s anomaly

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7 7
0
7
0
1
2
0
1
2
0
3
2
4
3
2
0
3
2
0
1
7
0
1
7 0 1 2 3 0 4 2 3 0 3 2 1 2 0 1 7 0 1
0
Number of page fault = 9

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7 7
0
7
0
1
2
0
1
2
0
3
4
0
3
0
3
2
1
3
2
7
0
1
7 0 1 2 3 0 4 2 3 0 3 2 1 2 0 1 7 0 1
0
Number of page fault = 12
4
0
2
4
3
2
1
0
2

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7
0
7
1
0
7
2
1
0
7
0
3
2
1
7
7 0 1 2 0 7
3
3
2
1
0
7
7
0
3
2
1

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