NoC中负载均衡的AVOQ路由器设计

针对片上网络中使用虚拟输出队列(VOQ)机制的路由器在网络拥塞时存在的头阻塞问题,提出负载均衡的AVOQ路由器架构。首先,输入缓冲区仍使用VOQ机制来处理头阻塞问题。其次,在路由计算模块自适应地选择输出端口,确保数据从较不拥塞的端口输出;在单个虚通道内自适应地读取数据包,确保下游不拥塞的流量能够在网络里流通。实验结果表明,相较于虚通道路由器和VOQ路由器,AVOQ路由器平均延时最多减少83.2%和57.1%,吞吐率最多增加72.7%和33.3%,功耗和面积开销可接受。该方案通过两个层级的自适应均衡全网的流量分布,缓解拥塞,进而降低头阻塞出现的可能性,并在头阻塞出现时消除其影响,提升网络性能。

Design of load balancing AVOQ router in network on chip

When congestion occurs in the network,VOQ routers still suffer a certain degree of head-of-line blocking (HoL) problem in the network-on-chip (NoC).Aiming at this issue,we propose the load-balancing AVOQ router architecture.Firstly,the VOQ mechanism is kept to deal with the HoL problem.Secondly,a flexible output port can be picked up in the routing computing module,making sure that the dada is ported out to the less congested road and a single virtual channel (VC) can read the packet adaptively,so that the less congested flow in the downstream can be transmitted.The experimental results show that,compared to the VC router and the VOQ router,AVOQ router reduces the average latency by 83.2％ and 57.1％ and improves the throughput by 72.7％ and 33.3％ at most,while the area overhead and power consumption are affordable.By the use of above adaptive mechanism,the network load is balanced and the congestion is relieved,and the appearing of the HoL is decreased.Moreover,the impact of HoL is eliminated as long as it appears,and the network performance is improved greatly.