摘要
代理缓存的替换策略事实上可以看做排序问题 ,排序的标准可能有多种 ,寻找一个好的代理缓存的替换策略就是寻找一个能够反映真实 Web访问特性的标准 .基于文档大小的替换策略是一种简单实用的策略 ,但是并未全部利用 WWW访问特性 .根据在代理缓存日志中对各种访问特性的分析 ,使用文档大小、访问频率、文档访问剩余寿命作为计算文档价值的要素 ,提出了一种新的替换策略 ,这种策略同时具有较高的文档命中率和文档字节命中率 ,最后给出了基于日志的模拟 .
Proxy cache replacement policy can be thought as a sorting problem, but there are many sort standards. The procedure to find a good replacement policy is a procedure to find a good sort standard for sorting. Replacement policy based on document size is a simple and better replacement policy, but it has not utilized all the WWW access characteristics. According to the analysis to Proxy Server logs, a new replacement policy is proposed, which uses document size, access frquency and document access remain life as its computing elements. It can achieve both high document hit rate and document byte hit rate. It is named Predict Size replacement policy because it can use document remain life to predict the next access of this document. The relationship between document size and access frquency is discussed. It also determine the relationship between refresh document and its access frequency. The formula to compute the remain life of a document is educed by using probability theory. Finally, simulation based on access log is given.
出处
《计算机研究与发展》
EI
CSCD
北大核心
2002年第10期1178-1185,共8页
Journal of Computer Research and Development
