HCAPP: Scalable Power Control for Heterogeneous 2.5D Integrated Systems

Package pin allocation is becoming a key bottleneck in the capabilities of designs due to the increased bandwidth requirements. 2.5D integration compounds these package-level requirements while introducing an increased number of compute units within the package. We propose a decentralized power control implementation called Heterogeneous Constant Average Power Processing (HCAPP) to maintain the power limit while maximizing the efficiency of the package pins allocated for power. HCAPP uses a hardware-based decentralized design to handle fast power limits, maintain scalability and enable simplified control for heterogeneous systems while maximizing performance. As extensions, we evaluate a software interface and the impact of different accelerator designs. Overall, HCAPP achieves 7% speedup over a RAPL-like implementation. The power utilization improves from 79.7% (RAPL-like) to 93.9% (HCAPP) with this design. A priority-based static software control methodology alongside HCAPP provides average speedups of 8.3% (CPU), 5.4% (GPU), and 12% (Accelerator) for the prioritized component compared to the unprioritized version.