Job management system (JMS) is an important part of any supercomputer. JMS creates a schedule for launching jobs of different users. Actual job management systems are complex software systems with a number of settings. These settings have a significant impact on various JMS metrics, such as supercomputer resources utilization, mean waiting time of a job in queue, and others. Various JMS simulators are widely used to study the influence of JMS settings or modifications, new scheduling algorithms, jobs input stream parameters or available computing resources for JMS efficiency metrics. The article presents the comparative analysis results of the actual JMS simulators (Alea, ScSF, Batsim, AccaSim, Slurm simulator) and their application areas. The authors consider new ways to use the JMS simulator as a scientific service for researchers. With such a service, the researchers are able to study various hypotheses about JMS efficiency, algorithms or parameters. This gives the folowing: (1) research is performed on the service side around the clock, (2) the simulator accuracy or adequacy is provided by the service, (3) the research results reproducibility is ensured, and the simulator-as-a-service becomes a single entry point for the researchers.