一种改进的BFT型片上网络拓扑结构-计算机系统应用.PDF

计 算 机 系 统 应 用 2011 年 第 20 卷 第 10 期 一种改进的BFT 型片上网络拓扑结构① 1 1 2 1 周文科 ，尤志强 ，邝继顺 ，刘 鹏 1(湖南大学 软件学院，长沙 410082) 2(湖南大学 计算机与通信学院，长沙 410082) 摘 要：针对片上网络(NoC)资源节点之间通信的局部性，提出改进的蝴蝶型胖树（BFT ）拓扑结构XBFT 及相 应的路由算法。该结构在 BFT 结构的基础上改变边的连接关系，减少了路由节点数和物理连接链路数，理论分 析表明，在 64 个 IP 核的 NoC 中，XBFT 较 BFT 路由器数目减少了 14.3%，物理链路数减少了 10.7%，XBFT 结 构比 BFT 结构拥有较小的面积开销和较低的布线难度。实验采用 gpNocsim 模拟器，对 64 节点的网络，基于局 部负载模式和均衡负载模式进行性能比较。实验结果表明，局部负载模式下，当包注入速率低于 0.6 时，XBFT 结构与 BFT 性能相当，随着包注入速率继续增加，XBFT 性能优于 BFT 。均衡负载模式下，当包注入速率低于 0.4 时，XBFT 网络性能比BFT 稍优，包注入速率大于 0.4，XBFT 网络性能比BFT 稍差。 关键词：片上网络；拓扑结构；路由算法；BFT Improved BFT Topology for Network on Chip 1 1 2 1 ZHOU Wen-Ke , YOU Zhi-Qiang , KUANG Ji-Shun , LIU Peng 1(Software School, Hunan University, Changsha 410082, China) 2(School of Computer and Communication, Hunan University, Changsha 410082, China) Abstract: This paper presents an improved BFT topology, XBFT, and a routing algorithm to point at the local communication of network-on-chip. The new structure changes some edges link, substracts the number of routers on the BFT topology to form XBFT. The theoretical analysis result shows that when the network size is 64 the number of routers of XBFT topology are less 14.3% than the number of routers of BFT topology and the number of physical links of XBFT topology are less than 10.7% the physical links of BFT topology. The new structure has less area cost and less layout cost than the BFT structure. Simulator analysis bases on gpNocsim using local traffic pattern and uniform traffic pattern, when the network size is 64. The simulation result shows for local traffic pattern, the average latencies of XBFT topology is less than the average latencies of BFT topology, when the injection rate of package less than 0.6, the XBFT and BFT topology