Looking for More Efficient Web Applications

Currently I am working on building an API for a project. Right now, I do it by using PHP and I return JSON data from the API. PHP is an interpreted language, its obvious to be slower than compiled languages. I need to handle much more server requests than PHP does. I have not tested the server request capacity of PHP codes, however what my concept says is compiled language are faster than interpreted languages and so compiled languages can handle more server requests. I am inclined to Java for this. Basics Java is done by me. So, lets get into some framework. For the start, I would grab Spring framework and let's see how this framework helps me get my need; implementing back-end API in Java. I just want the server side to be more efficient to handle the clients requests. I have tested the execution time of these two different powerful languages. Starting spring framework from the very first "HelloWorld" Spring Application.