Analytical Modelling and Performability Analysis for Cloud Computing Using Queuing System

In recent years, cloud computing becomes a new computing model emerged from the rapid development of the internet. Users can reach their resources with high flexibility using the cloud computing systems all over the world. However, such systems are prone to failures. In order to obtain realistic quality of service (QoS) measurements, failure and recovery behaviours of the system should be considered. System's failures and repairs are associated with availability context in QoS measurements. In this paper, performance issues are considered with the availability of the system. Markov Reward Model (MRM) method is used to get QoS measurements. The mean queue length (MQL) results are calculated using the MRM. The results explicitly show that failures and repairs affect the system performance significantly.