Whether a change in workload of a database system has occurred can be determined. Investigative queries are formulated. Each investigative query is adapted to test a different resource or a different combination of resources of the database system. The investigative queries are run when the database system is in an unloaded state to acquire unloaded performance metrics. The investigative queries are run when the database system is in a loaded state to acquire loaded performance metrics. Whether executing a current workload of the database system, using a current configuration of the database system, will likely result in a problem developing at a later point in time can also be determined. Simultaneously with actual execution of the current workload on the database system using the current configuration, a simulation of execution of the current workload using the current configuration is performed. The simulation is performed more quickly than the actual execution.