Energy-optimizing source code transformations for operating system-driven embedded software

This paper proposes four types of source code transformations for operating system (OS)-driven embedded software programs to reduce their energy consumption. Their key features include spanning of process boundaries and minimization of the energy consumed in the execution of OS services—opportunities which are beyond the reach of conventional compiler optimizations and source code transformations. We have applied the proposed transformations to several multiprocess benchmark programs in the context of an embedded Linux OS running on an Intel StrongARM processor. They achieve up to 37.9% (23.8%, on average) energy reduction compared to highly compiler-optimized implementations.