We considered a system with edge devices such as mobile phones, laptops, and an edge server. Each edge device has an oƯload queue wirelessly connected to the server. We use the system to perform inference on the arriving tasks. To do so, we deploy each device with a pre-trained ML model. As the edge server operates remotely and has abundant resources such as power and computing, we deployed a powerful ML model, Large ML or L-ML. As the edge devices are resource-constrained, we deployed a smaller, less accurate ML model (S-ML), which consumes fewer resources. Such a setup is known as Hierarchical Inference. We use the system to perform image classification and aim to improve its overall inference accuracy by maintaining queue stability. The images arrive at the devices at random. As soon as a new task arrives, the device classifies the task as having arrived. The device, after classification, gives out the tasks' class with some confidence. As the task's ground truth is unknown and the S-ML deployed is not accurate, all the tasks processed might not be correct. Hence, an oƯloading strategy is essential to improve the overall system performance.
Utilizing the prior works, we designed a strategy that utilizes the confidence values of tasks to perform inference. Our strategy significantly improved the system accuracy and maintained queue stability throughout. Compared with the state-of-the-art techniques, our strategy was more accurate than the rest.