Page Replacement Algorithms
Definition – when a page is being considered for replacement, its reference bit is examined; if this bit is 0, the page is replace. Otherwise, it is passed and another page is examined
Implementation – circular queue
Enhanced Second-Chance Algorithm
Definition – second chance algorithm that uses the modify bit as well
Four possible classes determined using modify bit and reference bit combinations
Preference given to those pages that have been modified to reduce the number of I/Os required