Evaluating the impact of Permanent Faults in a GPU running a Deep Neural Network

Currently, Deep Neural Networks (DNNs) are fun-damental computational structures deployed in a wide range of modern application domains (e.g., data analysis, healthcare, automotive, robotics). The computational complexity is inherent in these cognitive models, which demand high-performance devices like Graphics Processing Units (GPUs). Therefore, the implementation of DNNs on GPU devices is becoming increasingly frequent, even for cutting-edge safety-critical applications (e.g., autonomous and semi-autonomous cars). Thus, the reliability evaluation of these applications is mandatory because several phenomena (including aging) may produce permanent defects in the GPU, thus inducing the DNN to produce wrong results. Until now, the effects of permanent faults on DNNs have been mainly investigated at the application level, only, e.g., acting on the parameters of the network. This paper presents an environment allowing for the first time a more detailed experimental evaluation of the impact of permanent faults in a GPU on the reliability of a DNN running on it, based on considering faults at the architectural level. The results of the fault injection campaigns we performed on the GPU register files are compared with those at the application level, proving that the latter ones are generally optimistic.