The Y-architecture: Yet Another On-Chip Interconnect Solution

In this paper, we propose a new on-chip interconnect scheme called Y-architecture, which can utilize the on-chip routing resources more efficiently than traditional Manhattan Interconnect Architecture by allowing wires routed in three directions (0°, 60°, and 120°). To evaluate the efficiency of different interconnect architectures, we assume mesh structures with uniform communication demand for communication and develop a multi-commodity flow (MCF) approach to model the on-chip communication traffic. The throughput of mesh structure is used to measure the communication capabilities of different interconnect architectures. We also extend the combinatorial MCF algorithm in [5] to compute the optimal routing resource allocations for different interconnect architectures. The experiments show that: (1) Compared with Manhattan architecture, the Y-architecture demonstrates a throughput improvement of 30.7% for square chip. The throughput of meshes using Y-architecture is only 2.5% smaller than that of meshes using more complicated X-architecture. (2) A chip with the shape of a convex polygon produces better throughput than a rectangular chip: For Y-architecture, a hexagonal chip provides 41% more throughput than a squared chip using the Manhattan architecture. For X-architecture, an octagonal chip produces 31% more throughput than a squared chip using the Manhattan architecture. For Manhattan architecture, a diamond chip achieves a throughput improvement of 19.5% over the squared chip using the same interconnect architecture. (3) Compared with Manhattan architecture, the Y-architecture reduces the wire length of a randomly distributed two pin net by 13.4% and the average wire length of Y-architecture is only 4.3% more than that of the X-architecturePre-2018 CSE ID: CS2002-071