基于软件的网络处理器的路由高速缓存算法研究  

Software-Based Route Cache Algorithm for Network Processors

作　　者：刘祯[1] 刘斌[1] 郑凯[1] 

机构地区：[1]清华大学计算机科学与技术系,北京100084

出　　处：《软件学报》2007年第12期3115-3123,共9页Journal of Software

基　　金：Supposed by the National Natural Science Foundation of China under Grant Nos.60373007;60573121(国家自然科学基金);the China/Ireland Science and Technology Collaboration Research Fund under Grant No.CI-2003-02(中国-爱尔兰政府间国际科技合作项目);the Specialized Research Fund for the Doctoral Program of Higher Education of China under Grant No.20040003048(高等学校博士学科点专项科研基金);the Cultivation Fund of the Key Scientific and Technical Innovation Project under Grant No.705003(高等学校科技创新工程重大项目培育资金项目)

摘　　要：路由器需要以较低的代价灵活、高速地实现路由查找这一基本功能.为网络处理器设计了一种基于软件的路由查找高速缓存算法.网络处理器片上高速存储器中的一部分空间被划分出来,由指令代码来维护一个路由查找结果缓存表.通过选择合适的哈希函数,平衡表项之间的冲突并刷新复杂度,该算法可以缩短路由查找的延迟,减少多处理单元对存储器总线的竞争,为其他网络应用提供更多的处理时间.基于真实网络流量的实验表明,即便每个处理单元中仅有少量表项,网络处理器的吞吐量仍然可以得到有效的提升.Routers require fast and flexible route table lookup for incoming packets at relatively low cost, This paper describes a software-based route cache algorithm for network processors, Part of the on-chip high-speed memory space is allocated and programmed into a caching table for temporal storage of route lookup results. A suitable hash function can make a good balance between cache miss rate and update complexity, which shortens the average search time, reduces the contentions on memory bus and leaves more headroom for other network applications. Experiments with real-life packet traces show that the packet throughput of a network processor can be greatly improved with only a small number of route cache entries per processing element,

关 键 词：路由高速缓存 网络处理器 路由查找 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]