Cloud computing has been emerging as a new technology. In a distributed computing perspective cloud is similar to client-server services like web-based services and uses virtualized resources for execution. The widespread use of internet technology has focused attention on quality of service, especially the response time experienced by the end user. We demonstrate the performance degradation of traditional web hosting with time varying user requests directly affecting the response time. We also show how this issue could be addressed by a web-server hosted on a cloud using control algorithms for Load balancing and Elasticity control developed to maintain the desired response time within acceptable limit. Our experimental setup hosts a web server on an open source Eucalyptus cloud platform. To evaluate the control system performance we use the web server benchmarking tool called httperf and autobench for automating the process of benchmarking. © 2013 IEEE.