| 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. |
| 关键词: 路由高速缓存 网络处理器 路由查找 |
| DOI： |
| 分类号: |
| 基金项目:Supported 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) |
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| Software-Based Route Cache Algorithm for Network Processors |
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LIU Zhen,LIU Bin,ZHENG Kai
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| Abstract: |
| 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. |
| Key words: route cache network processor route lookup |
