Battery optimization vs energy optimization: which to choose and when?

— Batteries are non-ideal energy sources – minimizing the energy consumption of a battery-powered system is not equivalent to maximizing its battery life. We propose an alternative interpretation of a previously proposed battery model, which indicates that the deviation from ideal behavior is due to the buildup of “unavailable charge” during the discharge process. Previously, battery-aware task scheduling algorithms and power management policies have been developed, which try to reduce the unavailable charge at the end of a given workload. However, they do not account for the occurrence of rest periods (user enforced, naturally occurring, or due to finite load horizon), which are present in a variety of workloads. We first obtain an analytical bound on the recovery time of a battery as a function of the extent of recovery. Then, we shown that the effect of the rest periods is to reduce the improvement of battery-charge optimizing techniques over traditional energy-optimizing ...

• Type: Conference
• Year: 2005
• Where: ICCAD
• Authors: Ravishankar Rao, Sarma B. K. Vrudhula
• Keywords: Battery-aware Task Scheduling, Energy Consumption, Hardware, ICCAD 2005, Unavailable Charge