Design and implementation of a highly configurable and efficient simulator for job schedulers on supercomputers

The supercomputers maintained by the Juelich Supercomputing Centre (JSC) are used byscientists for simulation projects in computational science and engineering. These systemsare run in batch mode and are shared among all active users. Jobs are submitted to thejob scheduler, which decides for each job the time of execution. It manages running andwaiting jobs, sorts them by a given priority and executes the jobs by ftting them intothe current system state. For users it is often difficult to understand the job scheduler'salgorithm. Thus, a prediction of the future system allocation of currently running andqueued jobs is valuable. It helps users to plan job submissions and supports administratorsby optimising the system load. ..