Nginx (pronounced engine x) is a web server with a strong focus on high concurrency, performance and low memory usage. It can also act as a reverse proxy server for HTTP, HTTPS, SMTP, POP3, and IMAP protocols, as well as a load balancer and an HTTP cache.

Configuration Information.

worker_processes: The number of NGINX worker processes. In most cases, running one worker process per CPU core works well. This can be achieved by setting this directive to “auto”. There are times when you may want to increase this number, such as when the work processes have to do a lot of disk I/O. The default is 1.

Also this controls number of worker processes Nginx is running. Set worker_processes = number of processors in your system. To find out how many processors you have on your server, run the following command:

grep processor /proc/cpuinfo | wc -l

Current Configuration

worker_processes auto;

worker_connections

If you are running very high traffic sites, its better to increase value of worker_connections. Default is 768. Theoretically, nginx can handle max clients = worker_processes ** worker_connections

We use worker_connections = 10240

worker_connections  10240;

worker_rlimit_nofile

Increase number of files opened byworker_process. This directive is not present by default. You can add it in /etc/nginx/nginx.conf in main section (belowworker_processes)

We use worker_rlimit_nofile 100000;

worker_rlimit_nofile 100000;

keepalive_requests: The number of requests a client can make over a single keepalive connection. The default is 100, but a much higher value can be especially useful for testing when the load generating tool is sending many requests from a single client.

Current we use keepalive_requests 20480;

#  Use this value for testing once done comment it.
keepalive_requests 20480;

Setting access_log with buffer. Write the data to file once we have reached the buffer. I/O Operations slow down processing.

    access_log  /var/log/nginx/access.log  main buffer=10m;

More Information Below.

  • http://www.slashroot.in/nginx-web-server-performance-tuning-how-to-do-it
  • https://rtcamp.com/tutorials/nginx/optimization/
  • http://nginx.com/blog/tuning-nginx/
  • https://www.digitalocean.com/community/tutorials/how-to-optimize-nginx-configuration