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Unlock all 12 →🧠 Memory & Page ReplacementFree
Step through FIFO, LRU & Optimal page replacement. See faults, hits and frame state per reference.
Page faults
12
Hits
8
Fault rate
60%
Faults by algorithm (same input)
FIFO
15
LRU
12
Optimal
9
Optimal is the theoretical best — no real OS can see the future. Compare how close LRU gets.
Frame trace
20/20
7
7
F
0
7
0
F
1
7
0
1
F
2
2
0
1
F
0
2
0
1
H
3
2
0
3
F
0
2
0
3
H
4
4
0
3
F
2
4
0
2
F
3
4
3
2
F
0
0
3
2
F
3
0
3
2
H
2
0
3
2
H
1
1
3
2
F
2
1
3
2
H
0
1
0
2
F
1
1
0
2
H
7
1
0
7
F
0
1
0
7
H
1
1
0
7
H
F = page fault · H = hit · purple = page just loaded
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