Abstract: Quality (QoS) prediction is one of the most important research
topics of workflow. In this paper, we propose a stochastic model to evaluate
QoS (make-span, reliability and cost) of workflow systems based on QWF-net,
which extends traditional WF-net by associating tasks with firing-rate,
failure-rate and cost-coefficient. Through a case study, we show that our
framework is capable of modeling real-world workflow-based application. Also,
Monte-carlo simulation in the case study indicates our analytical methods are
consistent with simulation. We also present a sensitivity analysis technique to
identify QoS bottleneck.The paper concludes with a comparison between our
approach and related work.
