适用于虚通道路由器的高性能round-robin仲裁器

分析了交换结构规模不同的2类典型的虚通道路由器体系结构,指出了交换结构规模对调度机制和仲裁器体系结构的显著影响.在轮转(round-robin)仲裁器PPE的基础上,提出了分别适用于上述2类路由器的改进型PPE仲裁器体系结构.改进型仲裁器将原有关键路径中的处理步骤转移到非关键路径中,并行实现了关键路径中的重要处理步骤,通过缩短关键路径改善了仲裁器的性能;同时通过调整仲裁流程消除了上述改进对资源成本的负面影响.基于TSMC 0.35μm CMOS工艺实现了不同规模的PPE和2种改进型仲裁器体系结构.实验结果表明上述2种改进型仲裁器比PPE仲裁器的性能分别提高12%和17%以上,并且在多数情况下同时减少了实现面积.

High performance round-robin arbiter for virtual channel router

Two typical virtual-channel router architectures were analyzed, whose switch fabrics were in different scales. The scale of switch fabric was indicated to lay great impact on scheduler and arbiters in the router. Two arbiter architectures were proposed as variations of PPE, a round-robin arbiter. By moving some steps on the critical paths to the non-critical paths and having some critical steps parallelized, the proposed variations shortened the critical paths over PPE to improve the performance. Some steps were adjusted, so that the side-effect on area caused by above modifications was eliminated. All arbiters including PPE and the proposed variations were evaluated in several scales, using TSMC 0.35μm CMOS technology. The results show that the proposed ones improve the performance by more than 12% and 17% over PPE respectively, and also have less area cost in most cases.