RB-OLITS: A Worst-Case Reorder Buffer Size Reduction Method for 3D-NoC Based on Ohm's Law-Like Traffic Splitting
30th International Teletraffic Congress (ITC 30), Vienna, Austria, (2018)Abstract
Higher link bandwidth provided by three-dimensional Network-on-Chip (3D-NoC) relies on multi-path routing and traffic splitting, which inevitably leads to out-of-order packet delivery problem when facing unbalanced traffic congestion. Therefore, a reordering mechanism, often requiring reorder buffers, is necessary to guarantee in-order delivery of packets. The reorder buffers are expensive in terms of both resource and power consumption, hence it is of great significance to reduce the reorder buffer size in the worst case. In this paper, we propose a improved Ohm's Law-like traffic splitting method, named RB-OLITS, for reducing the worst-case reorder buffer size. The traffic splitting configuration is obtained according to the parallel resistance theory. Experimental results show that RB-OLITS has reduced the worst-case reorder buffer size by 19.09% in average compared with OLITS. Meanwhile, the worst-case delay bound is not degraded by using RB-OLITS, as the worst-case delay bound of the same target flow is slightly improved by 1.59% in average.