BlitzCoin: Fully Decentralized Hardware Power Management for Accelerator-Rich SoCs

On-chip power-management techniques have evolved over several processor generations. However, response time and scalability constraints have made it difficult to translate existing power-management strategies to current or next-generation System-on-Chip (SoC) architectures, which are expected to comprise tens to hundreds of cores and accelerators. In this work we present BlitzCoin, a fully decentralized hardware power-management strategy for large, accelerator-rich SoCs, coupled with optimized unified voltage and frequency regulation. We evaluated BlitzCoin through RTL simulations of multiple SoCs targeted toward different application domains. The results are further validated through silicon measurements of a fabricated 12 nm many-accelerator SoC that includes BlitzCoin. Our evaluations show that BlitzCoin is markedly faster, with 8× to 12× lower response times, which provides 25%-34% throughput improvement and allows for scaling to 7 × to 13 × larger SoCs compared to state-of-the-art centralized power-management strategies, all with an area overhead of <1%.