移动数据库中一种缓存策略

基于失效报告的广播技术在支持长时间断接操作中比较有效,但是对于两个失效报告间隔中提出的查询请求,需要等到下一失效报告广播后才能对其进行回复,造成查询的长时间延迟和不必要的带宽浪费.为解决这个问题,对经典的缓存算法进行改进,提出一种改进算法——低查询延迟缓存失效报告算法,并进行模拟试验,证明其在增加缓存命中率、减小查询延迟和增大系统吞吐量等方面的优越性.

A Cache Strategy in Mobile Databases

The research on mobile databases cache algorithms is generally based on traditional algorithms,which is based on the invalidation report technology. It is useful for a long time disconnection operation,but for a query between two IR intervals,it should not be answered until the next IR arrival. Thus,it generates a long time query delay and unnecessary bandwidth waste.For solving the problem,the classical cache algorithms are improved,and an improved algorithm called LQLCIR is proposed.The simulation experiment has testified its superiority in increasing the cache ratio,decreasing query delay and augmenting the system throughput etc.