A profile-based energy-efficient intra-task voltage scheduling algorithm for hard real-time applications

Intra-task voltage scheduling (Intra VS), which adjusts the supply voltage within an individual task boundary, is an effective technique for developing low-power applications. In this paper, we propose a novel intra-task voltage scheduling algorithm for hard real-time applications based on average-case execution information. Unlike the original Intra VS algorithm where voltage scaling decisions are based on the worst-case execution cycles, the proposed algorithm improves the energy efficiency by controlling the execution speed based on average-case execution cycles while still meeting the real-time constraints. The experimental results using an MPEG-4 decoder program show that the proposed algorithm reduces the energy consumption by up to 34% over the original Intra VS algorithm.