Backlog Bound Analysis for Virtual-Channel Routers

Backlog bound analysis is crucial for predicting buffer sizing boundary in on-chip virtual-channel routers. However, the complicated resource contention among traffic flows makes the analysis difficult. Because conventional simulation-based approaches are generally incapable of investigating the worst-case scenarios for the backlog bounds, we propose a formal analysis technique. We identify basic buffer use scenarios and propose corresponding analysis models to formally deduce per-buffer backlog bound using network calculus. A topology independent analysis technique is developed to convey the per-buffer backlog bound analysis step by step. We further develop an algorithm to automate the analysis procedure with polynomial complexity. A case study shows how to apply the technique and the analytical bounds are tight.