Unixcop published a tutorial about tuning the Nginx webserver for best performance.

How get the best performance from the Nginx Server

You can tune almost any setting, but this post concentrates on the few settings for which tuning benefits the most users. There are settings that we recommend you change only if you have a deep understanding of NGINX and Linux. So, you will know How get the best performance from the Nginx Server 

How get the best performance from the Nginx Server - Unixcop the Unix / Linux the admins deams