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Self doubt:

What is the rule or keyb point we should keep in mind while solving problems on LRU page replacement algorithm? Please explain with examples.
in Operating System 170 views

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Best answer

My definition about LRU is Replace the page which one is Long-ago Used

1) no.of pages already loaded in the memory

              given reference string is 1,2,4,5,6,1,2,3..... using demand-paging said  that already two pages brought in main memory 1 ,2 and 1 is brought before 2

          then

           in the reference string very first 1 and 2 are hits but not the page faults 

2) which page is long-ago used

            given reference string is 1,2,4,5,6,1,2,3..... think each reference is in different month first 1 is in jan, first 2 is in feb, 4 is in mar, 5 is in apr, 6 is in may, second 1 is June , second 2 is in July etc... if a hit occurs consider the page respective month is updated to new one ( 1 is June and 2 is July in this example ). if a page fault occurs replace the page with which have long-ago referred...


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