Cloud computing provides an ability to access shared resources and common infrastructure, over the network to perform operations that meet changing business needs. Organizations are becoming interested in leveraging cloud services as it leads to increase in flexibility and scalability of the IT services that are delivered to customers. In the meantime, Cloud computing also brings new issues and challenges in performance and scalability measurement due to its special features such as elasticity and scalability.It focus on analysing the performance and scalability of cloud based application. It also shows the applicability of the Blazemeter framework for testing performance of web or cloud based applications. It reveals that there are specific considerations to be made while performing testing operations on cloud environment. This paper reports one case study for selected web application deployed on cloud platform to demonstrates the application results for SaaS performance and scalability evaluation. The results aimed at analyzing the performance and scalability by varying the load and increasing number of users.

Keywords : Cloud Computing, QoS Metrics, Performance Analysis, Scalability Analysis.