小缓存下一种基于推送方式的多接口输出缓存设置策略

Push based buffer setting strategy for high density linecard of small buffer size

以往路由器线卡的缓存技术研究主要集中于如何构建高速、大容量的缓存上,随着小缓存策略主导下一代路由器设计成为可能,研究高效的缓存设置策略以提高小缓存的使用效率就成为研究的重点。针对高接口密度线卡提出了一种基于推送方式的输出端缓存池策略。为了从理论上对该策略进行评估,提出了一种基于丢包率指标的缓存收益函数,能够在小缓存环境下对缓存的使用效率做出统一评估。评估结果表明:该策略能够消除以往策略的队头阻塞问题和反压机制问题,并且在小缓存环境下具有更好的缓存收益率,能够更经济地利用有限的缓存资源。

Much of the previous work on buffer design of router linecard mainly focus on how to implement large and fast packet buffers, however, lots of recent theories suggest that the optimal buffer size would no longer be a large one as expected, and a small buffer should be sufficient. A push based buffer setting strategy for high density linecard of small buffer size was presented, and a buffer-revenue function was introduced to give an evaluation on using efficiency of the small buffer. It is proved that the strategy can completely eliminate the HOL（header of line） blocking problem and the back-pressure mechanism of the existing strategies, moreover, the strategy can also get a better revenue when the buffer-revenue function is used to give an evaluation.