chttpd

A single-threaded HTTP/1.1 server written in C, which can manage over 55,000 requests per second on a mid-range desktop.

I got this performance by leaning heavily on Linux kernel features:

• epoll is used for I/O event notifications;
• sendfile is used to send files without an intermittent buffer;
• namespaces and pivot_root are used for filesystem isolation;
• TCP_CORK to group small send and sendfile calls together.

To elaborate on the namespace part a bit: the ./site/ directory becomes / for the chttpd process, which means if you request /index.html the file is actually located at /index.html as far as the server is concerned. No path processing needed.

I considered making it multithreaded, but honestly I'm not sure I even need to.

If you need more than 55,000 requests per second, use a real server like nginx. <3

Port 80?

The code, as-is, doesn't need root. But what if you want to run it on port 80?

1. Change the port from 8080 to 80.
2. (Re)build chttpd.
3. Run setcap CAP_NET_BIND_SERVICE=+eip chttpd (probably as root).

In theory it should work!

Performance

System configuration:

• Ryzen 5 7600
• 32GB DDR5-5400 (chttpd uses less than 5KB on my system, though)
• 2TB nvme SSD.

Performance test for a large number of small requests:

• Consistently over 55,000 requests/second.
• Response times: 0.0045s slowest / 0.0009s average / 0.0001s fastest.