The aim of this study is the analysis and presentation of some ideas on performance testing in Cloud Computing. Performance is an important factor in testing a web application. Performance testing in cloud computing is different from that of traditional applications. Our research methodology in this article includes an overview of existing works on testing performance in Cloud Computing, focusing on discussion that the traditional benchmarks are not sufficient to analyze performance testing in Cloud Computing. In this study we are focused mainly on analysis performance metrics in Cloud Computing, based on their characteristics such as elasticity, scalability, pay-per-use and fault tolerance, and then we discuss why needed new strategies for performance testing in Cloud Computing and creation of new benchmarks. From this study we conclude that the performance testing and evaluation should be performed using new models testing, which are created according to Cloud Computing characteristics and metrics.