LOTTERYBUS: A new high-performance communication architecture for system-on-chip designs

This paper presents LOTTERYBUS, a novel high-performance communication architecture for system-on-chip (SoC) designs. The LOTTERYBUS architecture was designed to address the following limitations of current communication architectures: (i) lack of control over the allocation of communication bandwidth to different system components or data flows (e.g., in static priority based shared buses), leading to starvation of lower priority components in some situations, and (ii) significant latencies resulting from variations in the time-profile of the communication requests (e.g., in time division multiplexed access (TDMA) based architectures), sometimes leading to larger latencies for high-priority communications. We present two variations of LOTTERYBUS: the first is a low overhead architecture with statically configured parameters, while the second variant is a more sophisticated architecture, in which values of the architectural parameters are allowed to vary dynamically. Our experiments investigate the performance of the LOTTERYBUS architecture across a wide range of communication traffic characteristics. In addition, we also analyze its performance in a 4x4 ATM switch sub-system design. The results demonstrate that the LOTTFRYBUS architecture is (i) capable of providing the designer with fine grained control over the bandwidth allocated to each SoC component or data flow, and (ii) well suited to provide high priority communication traffic with low latencies (we observed upto 85.4% reduction in communication latencies over conventional on-chip communication architectures).