If you are using nginx as your webserver, you are looking for a performance boost and better speed. nginx is fast by default, but you can optimize its performance and the performance of all parts (like PHP and MySQL) that work together with nginx. Here is a small, incomprehensive list of tips and tricks to configure your LEMP system (Linux, nginx, MySQL, PHP-FPM) for maximum performance. These tricks work for me, but your mileage may vary. Do not implement them all at once, but one by one and check what effect the modification has on your system's performance.