An increasing number of battery-powered devices that are used outdoors or in mobile systems put emphasis on the power and energy efficiency as a form of trade-off between application performance and system power consumption. However, lack of objective metrics for the evaluation of application performance degradation poses difficulties for managing such trade-offs in real-time applications. The proposed methodology introduces metrics for modeling of application performance and the technique for its control, enabling more efficient power–performance trade-off management. The methodology allows for selective system performance degradation and fine-grained control of system behavior in the power–performance domain by extending the set of operating point parameters controllable through real-time application. The utilization and the effectiveness of the proposed methodology is evaluated in a simulated environment for different scenarios of the application execution, including system operation above the utilization bounds.