A Scalable Parallel Q-Learning Algorithm for Resource Constrained Decentralized Computing Environments

The Internet of Things (IoT) is more and more becoming a platform for mission critical applications with stringent requirements in terms of response time and mobility. Therefore, a centralized High Performance Computing (HPC) environment is often not suitable or simply non-existing. Instead, there is a need for a scalable HPC model that supports the deployment of applications on the decentralized but resource constrained devices of the IoT. Recently, Reinforcement Learning (RL) algorithms have been used for decision making within applications by directly interacting with the environment. However, most RL algorithms are designed for centralized environments and are time and resource consuming. Therefore, they are not applicable to such constrained decentralized computing environments. In this paper, we propose a scalable Parallel Q-Learning (PQL) algorithm for resource constrained environments. By combining a table partition strategy together with a co-allocation of both processing and storage, we can significantly reduce the individual resource cost and, at the same time, guarantee convergence and minimize the communication cost. Experimental results show that our algorithm reduces the required training in proportion of the number of Q-Learning agents and, in terms of execution time, it is up to 24 times faster than several well-known PQL algorithms.