paging - How pages loaded in RAM other than after page-fault trap? -


i trying understand demand paging concepts , can't find answer. how page-fault rate can relatively small, if way os understand need particular page, fetch instruction , find out page not loaded ram? if page-fault rate small, how os manages load in ram right pages? how guesses in advance, particular page needed? thanks.

a demand paging system needs fetch each initialized page disk @ least once. once page loaded, needs unloaded if there demand physical memory.

in days of multi-user systems 4gb address spaces , 8mb of physical memory, there lot of paging.

now 8gb of memory pretty standard on single user system, there not paging there once was.


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