QoS prediction for dynamic reconfiguration of component based software systems

It is difficult to choose the appropriate reconfiguration approach to satisfy the Quality of Service (QoS) requirements of a software system if the properties of that approach are not known. This problem significantly restricts the application of dynamic reconfiguration approaches to mission-critical or non-stop systems, where QoS is a major performance indicator. This paper proposes a model to predict how the QoS of a running software system will be affected by dynamic reconfiguration and show how it out-performed the existing methods in this area in 3 aspects. First, unlike existing simulation based models, this prediction model was based on easily implemented mathematical functions. Second, compared with the time-consuming simulation approaches, QoS prediction using this model was achieved in a shorter timeframe. Third, unlike the existing approaches that are built on different platforms for individual scenarios, this model generalized QoS prediction onto a single virtual platform that was modeled by abstract hardware and software conditions. The proposed model has been verified by reconfiguration simulation to a reasonable level of accuracy and thus the viability and safety for the use of the model has been confirmed.