The C10k problem is a limitation that most web servers currently have, which limits the web server to being able to handle a maximum of about ten thousand simultaneous connections. This limitation is due to a combination of operating system constraints and web server software limitations.
A few web servers have been developed to counter the C10K problem:
- nginx, which relies on an event-driven (asynchronous) architecture, instead of threads, to handle requests (WordPress.com uses nginx to solve the C10K problem)
- Lighttpd, which relies on an asynchronous architecture to handle requests
- Cherokee, a lightweight web server
- Tornado, a non-blocking web server and web application framework
- Deft, asynchronous, non-blocking web server running on the JVM