CoAdapt: Predictable Behavior for Accuracy-Aware Applications Running on Power-Aware Systems

We present CoAdapt, a runtime that coordinates accuracy-aware applications, which expose accuracy/performance tradeoffs, with power-aware systems, which manage power/performance tradeoffs. This is a challenging problem because decisions made at one level affect, and often counteract, decisions made at the other, leading to unpredictable behavior. Prior approaches have coordinated application and system, but provide a guarantee in only a single dimension (i.e., just one of performance, power, or accuracy). In contrast, CoAdapt addresses the full performance/power/accuracy problem space with an adaptive runtime control system that guarantees behavior in any two of these dimensions, while optimizing the third. We implement CoAdapt on a Linux/x86 platform and show it predictably stabilizes to the desired behavior, adapts to phases in application workload, and supports dynamic changes to behavioral goals.