一种改进的自适应页面置换算法

AN IMPROVED ADAPTIVE PAGE REPLACEMENT ALGORITHM

研究缓冲区页面置换策略和算法(特别是自适应页面置换策略和算法),提出一种基于双管理链的自适应页面置换算法HA。HA算法是对DMC(2c)算法的改进,它引入动态置换点,同时,根据缺页失败数确定算法的工作链,并根据页面访问序列的局部特征选择效率较高的页面置换策略。实验结果表明,HA算法能有效地减少缺页失败数,降低缺页率,特别是在处理第三种模式的页面访问序列时,该算法的缺页率较改进前的算法可降低近30%。

In this paper we research on the replacement policy and algorithm of the pages in buffer,especially those of the adaptive pages,and then propose an improved adaptive page replacement algorithm based on double management links,HA.HA is an improvement of DMC（2c） algorithm,it introduces the dynamic replacement points and meanwhile determines its working link according to the number of page faults,and chooses a more effective page replacement policy based on the local features of page reference sequences.Experimental results show that HA can reduce the number and rate of page faults more effectively,especially when working on page reference sequences of pattern 3,this algorithm can reduce the rate of page fault by about 30% than the unimproved algorithm.