Modeling Complex User Behavior with the Palladio Component Model

The specification of workloads is required in order to evaluate performance characteristics of application systems using performance prediction approaches like the Palladio Component Model (PCM). One of the biggest challenges in workload modeling is to ensure that the modeled user behavior adequately resembles the real user behavior. However, PCM offers limited support to model such complex user behavior. Furthermore, reusing modeled activities is not possible. To overcome these limitations, workarounds are required. In order to avoid these workarounds, we extend the meta-model of the PCM Usage Model. We evaluate the extended PCM Usage Model by integrating it into our previous work on automatic extraction of workload specifications. Based on HTTP web logs, recorded from the standard industry benchmark SPECjEnterprise2010, instances of a domain-specific language (DSL) for modeling workload specifications are extracted. Afterwards, these instances are transformed to the extended PCM Usage Model. The evaluation shows that workload characteristics of the simulated workload match the measured workload with high accuracy.