EvolutionSim: An Extensible Simulation Toolkit for Microservice System Evolution

Recently, microservices architecture has become the mainstream software development and deployment architecture for most enterprises, with the advantages of continuous delivery/deployment. However, the inability of microservices systems to meet changing user requirements and other external factors can lead to a degradation of quality of service (QoS), necessitating microservice evolution to ensure QoS stability by adjusting the deployment structure and configuration of microservices through evolutionary means such as redeployment. In order to study different evolutionary problems, simulation of microservice evolution is critical because the flexibility and diversity of the simulation environment can provide a more prosperous experimental environment for the researchers involved compared single physical experiments and numerical experiments. However, existing simulators have limitations when it comes to simulating microservice evolution. They either lack the capability to support the simulation of microservice evolution or only provide simulation for specific evolutionary means, which limits their extensibility. To address this issue, this paper designs and implements a simulation toolkit EvolutionSim for MSS evolution based on discrete event. It aimes to simulate the running and evolution process of MSSs with the support of several evolutionary means. In addition, Experiments were carried out to compare the simulated results with the actual results, and the distribution was found to be similar by ADF test, which indicates that EvolutionSim can provide valid results. Moreover, three experimental scenarios were conducted to simulate three mainstream evolutionary means, and the results indicate that EvolutionSim can accurately simulate the effects of different evolutionary means on MSS.