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<title>Page Replacement Algorithms</title>
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		<h4>Least Recently Used Page Replacement</h4>

			In this algorithm page will be replaced which is least recently used.<br>
			Let say the page reference string 7 0 1 2 0 3 0 4 2 3 0 3 2 . Initially we have 4 page slots empty.<br>

			<ul>
				<li>Initially all slots are empty, so when 7 0 1 2 are allocated to the empty slots  = <b>4 Page faults</b></li>
				<li>0 is already their so = <b>0 Page fault</b></li>
				<li>when 3 came it will take the place of 7 because it is least recently used = <b>1 Page fault</b></li>
				<li>0 is already in memory so = <b>0 Page fault</b></li>
				<li>4 will takes place of 1 = <b>1 Page fault</b></li>
				<li>Now for the further page reference string = <b>0 Page fault</b> because they are already available in the memory.</b></li>
			</ul>

			Let us have a reference string: a, b, c, d, c, a, d, b, e, b, a, b, c, d and the size of the frame be 4.<br>
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			<img class="LRU" src="LRU.png"><br>

			There are 7 page faults using LRU algorithm.<br><br>

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