DynCNN: Application Dynamism and Ambient Temperature Aware Neural Network Scheduler in Edge Devices for Traffic Control

Abstract

Road traffic congestion increases vehicular emissions and air pollution. Traffic rule violation causes road accidents. Both pollution and accidents take tremendous social and economic toll worldwide, and more so in developing countries where the skewed vehicle to road infrastructure ratio amplifies the problems. Automating traffic intersection management to detect and penalize traffic rule violations and reduce traffic congestion, is the focus of this paper, using state-of-the-art Convolutional Neural Network (CNN) on traffic camera feeds. There are however non-trivial challenges in handling the chaotic, non-laned traffic scenes in developing countries. Maintaining high throughput is one of the challenges, as broadband connectivity to remote GPU servers is absent in developing countries, and embedded GPU platforms on roads need to be low cost due to budget constraints. Additionally, ambient temperatures in developing country cities can go to 45-50 degree Celsius in summer, where continuous embedded processing can lead to lower lifetimes of the embedded platforms. In this paper, we present DynCNN, an application dynamism and ambient temperature aware controller for Neural Network concurrency. DynCNN effectively uses processor heterogeneity to control the number of threads and frequencies on the accelerator to manage application utility under strict thermal and power thresholds. We evaluate the efficiency of DynCNN on three different commercially available embedded GPUs (Jetson TX2TM, Xavier NXTM and Xavier AGXTM) using a real traffic intersection’s 40 days’ dataset. Experimental results show that in comparison to all existing state-of-the art- GPU governors for two different CPU settings, DynCNN reduces the average temperature and power by ~12°C and 68.82% respectively for one CPU setting (Baseline1) and similarly, it improves the performance by around 31.2% compared to the other CPU setting (Baseline2).