Performability Analysis for Software-Intensive System Considering Variety of Tasks and Operation-Oriented Restoration

Abstract

In this paper, we discuss software performability evaluation considering the real-time property. The time-dependent behavior of the system alternating between up and down state is described by the Markov process. Then we incorporate the operation-oriented restoration scenario into the model, i.e., we consider the following two types of restoration: one is the restoration with debugging and the other is without debugging. Assuming that the software system can process the multiple tasks simultaneously, we also consider the variety of tasks in terms of the task arrival process and the processing time limit. We describe the arrival process of the tasks follows a nonhomogeneous Poisson process and treat the processing time limit as a random variable. We analyze the distribution of the number of tasks whose processes can be completed within the processing time limit with the infinite server queueing model. From the model, we derive several software performability measures considering the real-time property. Finally, we illustrate several numerical examples of the measures to investigate the impact of the variety of tasks and the operational restoration on the system performability evaluation.