This paper presents a framework to enable the energy-efficient execution of convolutional neural networks (CNNs) on edge devices. The framework consists of a pair of edge devices connected via a wireless network: a performance and energy-constrained device D as the first recipient of data, and an energy-unconstrained device N as an accelerator for D. Device D decides on-the-fly how to distribute the workload with the objective of minimizing its energy consumption while accounting for the inherent uncertainty in network delay and the overheads involved in data transfer. These challenges are tackled by adopting the data-driven modeling framework of Markov Decision Processes (MDP), whereby an optimal policy is consulted by D in O(1) time to make layer-by-layer assignment decisions. As a special case, a linear-time dynamic programming algorithm is also presented for finding optimal layer assignment at once, under the assumption that the network delay is constant throughout the execution of the application. The proposed framework is demonstrated on a platform comprised of a Raspberry PI 3 as D and an NVIDIA Jetson TX2 as N. An average improvement of 31% and 23% in energy consumption is achieved compared to the alternatives of executing the CNNs entirely on D and N. Two state-of-the-art methods were also implemented, and compared with the proposed methods.
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Energy-Efficient Mapping for a Network of DNN Models at the Edge
This paper describes a novel framework for executing a network of trained deep neural network (DNN) models on commercial-off-the-shelf devices that are deployed in an IoT environment. The scenario consists of two devices connected by a wireless network: a user-end device (U), which is a low-end, energy and performance-limited processor, and a cloudlet (C), which is a substantially higher performance and energy-unconstrained processor. The goal is to distribute the computation of the DNN models between U and C to minimize the energy consumption of U while taking into account the variability in the wireless channel delay and the performance overhead of executing models in parallel. The proposed framework was implemented using an NVIDIA Jetson Nano for U and a Dell workstation with Titan Xp GPU as C. Experiments demonstrate significant improvements both in terms of energy consumption of U and processing delay.
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- Award ID(s):
- 2008244
- PAR ID:
- 10425834
- Date Published:
- Journal Name:
- IEEE International Conference on Smart Computing
- ISSN:
- 2693-8340
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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