Abstract: A performance simulation infrastructure for predicting the performance of software systems separates the workload definition and performance evaluation components of the simulation into separate and distinct stages. Workload definitions are generated in the first stage as a sequence of associated resource usage requests (or “workload requests”). In a second stage, an evaluation engine receives the workload definition sequence and simulates the system performance, without continuously looping back to the workload definition generator for a new state of the workload. Scheduling simulation of request events to appropriate hardware models is deferred until the evaluation stage, thereby simplifying the workload definition operation.

Abstract: A performance prediction simulator gives effect to the resource contention among multiple resources in a simulated system by adjusting event durations appropriately. A resource topology tree defining the resource configuration of the system is input to the simulator. The simulator includes an evaluation engine that determines the amount of resource used during each simulation interval of the simulation and records the resource usage in a resource contention timeline, which can be displayed to a user. The amount of resource used during a simulation is also used to adjust the event duration calculations of the hardware models associated with each event.