OAPM: Fine-grained operand-aware power management with fast reaction time

Abstract

Power management is a crucial aspect of modern low power SoCs, but kernel-based approaches suffer from slow DVFS and power state adaptation. We propose OAPM, a power management scheme based on circuit-level operand activity that complements existing OS-based solutions with better system visibility. Operating at the cycle granularity, OAPM has very fast response time in requesting the appropriate power state via a two-stage algorithm. Simulations show potential savings of up to 70% when used with clock-gated Domino, depending on the activity profile.