Abstraction: This design require me use a most unusual swap algorithm. When swa...

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本次设计要求我使用最不经常使用页面淘汰算法。该算法在需要太太某一页是，首先淘汰到当前时间为止，被访问次数最少的那一页。这只要在页表中给每一页增设一个访问计数器即可实现。每当该页被访问时，访问计数器加1，而发生一次缺页中断时，则淘汰计数值最小的那一页，并将所有的计数器清零。-Abstraction: This design require me use a most unusual swap algorithm. When swap operation is demanded, this algorithm first swap the least accessed page up to present. To implement this algorithm, only need add a counter variable to eash page of the page table. When one page is accessed, the counter increase one. When page invalid interrupt occur, wash out the page with least count, then reset all the counters to zero.