Energy-Efficient Computation Offloading in MobileEdge Computing Systems with Uncertainties

TL;DR

This paper proposes a robust computation offloading method for mobile edge computing that accounts for uncertainties in network conditions, leading to significant energy savings on real devices.

Contribution

It introduces an uncertainty-aware offloading algorithm using extreme value theory and an $$-bounded approximation, improving energy efficiency under realistic conditions.

Findings

Lower energy consumption observed on Android devices.

Outperforms existing schemes in energy savings.

Effective handling of network uncertainties in MEC.

Abstract

Computation offloading is indispensable for mobile edge computing (MEC). It uses edge resources to enable intensive computations and save energy for resource-constrained devices. Existing works generally impose strong assumptions on radio channels and network queue sizes. However, practical MEC systems are subject to various uncertainties rendering these assumptions impractical. In this paper, we investigate the energy-efficient computation offloading problem by relaxing those common assumptions and considering intrinsic uncertainties in the network. Specifically, we minimize the worst-case expected energy consumption of a local device when executing a time-critical application modeled as a directed acyclic graph. We employ the extreme value theory to bound the occurrence probability of uncertain events. To solve the formulated problem, we develop an $\epsilon$-bounded approximation algorithm based on column generation. The proposed algorithm can efficiently identify a feasible solution that is less than (1+$\epsilon$) of the optimal one. We implement the proposed scheme on an Android smartphone and conduct extensive experiments using a real-world application. Experiment results corroborate that it will lead to lower energy consumption for the client device by considering the intrinsic uncertainties during computation offloading. The proposed computation offloading scheme also significantly outperforms other schemes in terms of energy saving.