利用ZIPF定律建立有效的WEB对象缓存机制

Effective Web Objects Caching Based on Zipf's Law

通过对Web通信量的分析,人们发现用户对Web对象的访问模式服从Zipf定律或类Zipf定律。在Web缓存的设计中,为得到所期望的Web对象命中率的要求,设计人员可以根据Zipf定律近似计算出相应的缓存大小。因此,Zipf定律为Web缓存结构的设计提供了重要的依据。适当的缓存大小结合P-LFU替换策略可以得到很高的Web缓存命中率。

According to measurements and statistics,Web objects access distribution in the Web is governed by Zipf's law or Zipf-like's law.This property provides an important tool in the design of Web caching architectures.Based on the law,designers can calculate appropriate cache sizes in order to achieve the desired hit ratios.The appropriate cache size combined with the P-LFU replacement policy can achieve a high Web cache hit rate.