...但此时应该把那个页面换出,则需要根据一定的页面置换算法(Page Replacement Algorithm)来确定。...(Least Recently Used, LRU) 2.3.1 基本思想 置换最近一段时间以来最长时间未访问过的页面。...LRU算法普偏地适用于各种类型的程序,但是系统要时时刻刻对各页的访问历史情况加以记录和更新,开销太大,因此LRU...
http://en.wikipedia.org/wiki/Page_replacement_algorithm#Least_recently_used 之前在网上看到过网友的一个C++实现,感觉不错,所以核心代码就采用了他的设计。相关链接如下: http://www.cppblog.com/red22/articles/62499.html 原作者通过两个MAP对象来记录缓存数据和LRU队列,注意其中的LRU队列并不是按照常用的方...
// remove the least frequently operated element ifc.len== c.cap{ c.eliminate() c.len-- } // insert in freqMap and itemMap c.insertMap(obj) // change minFreq to 1 because insert the newest one c.minFreq =1 // length++ c.len++ } } 插入一个新的 func(c *LFU)insertMap(obj i...
Over the years many algorithms have been proposed for page replacement. Each algorithm attempts to minimize the page fault rate while incurring minimum overhead. , In this paper we discuses at the traditional algorithms such as LRU. Least Recently Used (LRU) page replacement algorithm is most ...
此外,clock算法还有一系列的变种,参考https://en.wikipedia.org/wiki/Page_replacement_algorithm#cite_note-9 工作集(Working Set) 工作集的意思是,进程在时间段(t - x, t)内使用的内存页集合,也有可能是(t,t+x)所访问的页集合,因此应该将它们尽可能保存在内存中。工作集的实现依赖于OS提供Page Aging的支持...
此外,clock算法还有一系列的变种,参考https://en.wikipedia.org/wiki/Page_replacement_algorithm#cite_note-9 工作集(Working Set) 工作集的意思是,进程在时间段(t - x, t)内使用的内存页集合,也有可能是(t,t+x)所访问的页集合,因此应该将它们尽可能保存在内存中。工作集的实现依赖于OS提供Page Aging的支持...
The research indictaes that LRU page-replacement algorithm is very close to the ideal one in memory management of operating system. Based on this, the principle of matrix method, which is used to realize the LRU algorithms, is introduced and discussed in detail. Keywords: page replacement; LRU...
表 1 常用页面置换算法比较 Table1Algorithmcomparisonofcommonpagereplacement 置换算法 换进页面顺序 换出页面顺序 缺页次数 缺页率 OPT 231542 124 6 50% FIFO 231524352 231524 9 75% Clock 23152435 23154 8 67% LRU 2315432 3124 7 58% 可以看出 OPT 性能最好,但无法实现, LRU 是相对最好的页面置换算法...
README MemManage-Pro A command-line tool simulating FIFO, LRU, & VMS page-replacement algorithms in OS memory management. Features dual execution modes and an intuitive interface for streamlined user experience. Simply use the makefile and then run whichever algorithm you choose.About...
Although they outperform the traditional LRU policy in performance, they do not consider the access frequency of clean page, which will consequently result in poor I/O performance. In order to solve this problem, we present a new buffering algorithm in this paper, called CCF-LRU, which ...