As title.
There is a buffer pool with 3 pages that receives requests for the following page numbers:
2,4,4,2,5,2,1,1,3,1
The replacement policies are MRU and CLOCK. I am confused about how they work. Could someone show me? Thanks a lot~
update:
There is my solution following the MRU policy:
2
2 4
2 4
2 4
2 4 5
2 4 5
1 4 5
3 4 5
1 4 5
Is that right?
And following the LRU policies:
hit/miss?
2 m
2 4 m
2 4 h
2 4 h
2 4 5 m
2 4 5 h
2 1 5 m
2 1 5 h
2 1 3 m
2 1 3 h
Is that right?
There is my solution following the MRU policy... Is that right?
As per the definition of MRU mentioned by you, your MRU page replacement policy appears correct.
The replacement policies are MRU and CLOCK. I am confused about how they work. In this case(for 2,4,4,2,5,2,1,1,3,1 page numbers) :
In Clock page replacement policy, the OS circulates through pages, clearing reference bits and finding a page with reference bit set to 0.
Page number Reference bit
2 1
2,4 1,1
2,4 1,1
2,4 1,1
2,4,5 1,1,1
2,4,5 1,1,1
1,4,5 1,0,0
1,4,5 1,0,0
1,3,5 1,1,0
1,3,5 1,1,0
And following the LRU policies: hit/miss? Is that right?
YES, for the LRU page replacement, the page ordering as well as the number of hits and misses both are correct.