Stability Assessment Method Considering Fault Fixing Time in Open Source Project

Recently, open source software (OSS) are adopted various situations because of quick delivery, cost reduction and standardization of systems. Many OSS are developed under the peculiar development style known as bazaar method. According to this method, faults are detected and fixed by users and developers around the world, and the fixed result will be reflected in the next release. Also, the fix time of faults tends to be shorter as the development of OSS progresses. However, several large-scale open source projects have a problem that faults fixing takes a lot of time because faults corrector cannot handle many faults reports quickly. Furthermore, imperfect fault fixing sometimes occurs because the fault fixing is performed by various people and environments. Therefore, OSS users and project managers need to know the stability degree of open source projects by grasping the fault fixing time. In this paper, for assessment stability of large-scale open source project, we derive the imperfect fault fixing probability and the transition probability distribution. For derivation, we use the software reliability growth model based on the Wiener process considering that the fault fixing time in open source projects changes depending on various factors such as the fault reporting time and the assignees for fixing faults. In addition, we applied the proposed model to actual open source project data and examined the validity of the model. KeywordsReliability, Stochastic differential equation, Open source project.