Energy Consumption Optimization of Real-Time Embedded Systems

Minimizing energy consumption with guaranteeing real-time constraints in low-power embedded systems is gaining more importance as real-time applications become more widely used in embedded systems. Dynamic voltage scaling is a technique to reduce energy consumption by lowering supply voltage. However, lowering supply voltage may interfere with scheduling algorithms, so that tasks may not be successfully scheduled. In this paper, we formulate the problem of minimizing energy consumption for pre-scheduling as an optimization problem, and show that the problem is a nonlinear convex optimization with linear constraints which can be solved by sequential quadratic programming. By solving the problem, we can obtain the optimal supply voltage and successful scheduling of all tasks is guaranteed.