The following configuration sums up all the changes proposed in the preceding sections:

worker_processes 3;
worker_rlimit_nofile 8000;

events {
  multi_accept on;
  use epoll;
  worker_connections 1024;
}

http {
  sendfile on;
  aio on;
  directio 4m;
  tcp_nopush on;
  tcp_nodelay on;
  # Rest Nginx configuration removed for brevity
}

It is assumed that NGINX runs on a quad core server. Thus, three worker processes have been spanned to take advantage of three out of four available cores and leaving one core for other processes.

Each of the workers has been configured to work with 1,024 connections. Correspondingly, the nofile limit has been increased to 8,000. By default, all worker processes operate with mutex; thus, the flag has not been set. Each worker processes multiple connections in one go using the epoll method.

In the http section, NGINX has been configured to serve files larger than 4 MB using direct I/O, while efficiently buffering smaller files using Sendfile. TCP options have also been set up to efficiently utilize the available network.

$ siege -b -c 790 -r 50 -q http://192.168.2.100/hello

Transactions:               79000 hits
Availability:               100.00 %
Elapsed time:               24.25 secs
Data transferred:           12.54 MB
Response time:              0.20 secs
Transaction rate:           3257.73 trans/sec
Throughput:                 0.52 MB/sec
Concurrency:                660.70
Successful transactions:    39500
Failed transactions:        0
Longest transaction:        3.45
Shortest transaction:       0.00