I just recently completed my degree at Imperial College London and my masters project was on ‘Performance Evaluation of Cloud Services’ (yes, I didn’t even know what this mean’t when I chose the project).
Essentially what I tried to accomplish was to look at the performance and cost implications of hosting cloud computing applications. My main focus was on Amazon EC2 instances (they are used by major internet companies like Instagram). I used a fancy mathematical topic called queuing theory to try and model requests to EC2 instances and I looked at the response times for these requests. They were database and web server requests.
If you are more interested in my work and conclusions reached have a look at my report on Github here.