An Analysis of the Impact of Gating Techniques on the Optimization of the Energy Dissipated in Real-Time Systems

Abstract

The paper concerns research on electronics-embedded safety systems. The authors focus on the optimization of the energy consumed by multitasking real-time systems. A new flexible and reconfigurable multi-core architecture based on pipeline processing is proposed. The presented solution uses thread-interleaving mechanisms that allow avoiding hazards and minimizing unpredictability. The proposed architecture is compared with the classical solutions consisting of many processors and based on the scheme using one processor per single task. Energy-efficient task mapping is analyzed and a design methodology, based on minimizing the number of active and utilized resources, is proposed. New techniques for energy optimization are proposed, mainly, clock gating and switching-resources blocking. The authors investigate two main factors of the system: setting the processing frequency, and gating techniques; the latter are used under the assumption that the system meets the requirements of time predictability. The energy consumed by the system is reduced. Theoretical considerations are verified by many experiments of the system’s implementation in an FPGA structure. The set of tasks tested consists of programs that implement Mälardalen WCET benchmark algorithms. The tested scenarios are divided into periodic and non-periodic execution schemes. The obtained results show that it is possible to reduce the dynamic energy consumed by real-time applications’ meeting their other requirements.

Keywords

• real time
• multitask
• energy-efficient
• time-predictable
• safety systems
• hardware design