I don't think of this as a problem. Tornado is just a small and lightweight non-blocking HTTP server with a couple of convenient libraries. There are some prett

I don't think of this as a problem. Tornado is just a small and lightweight non-blocking HTTP server with a couple of convenient libraries. There are some pretty awesome, elegant solutions to the problem you point out, and I like to think of these as extensions to the small Tornado framework. One really cool one is http://thomas.pelletier.im/2010/08/websocket-tornado-redis/ http://thomas.pelletier.im/2010/08/websocket-tornado-redis/, which demonstrates how to use threading to support Redis pub/sub. For heavy computational tasks that aren't time-critical, you could have an accessory worker thread that chugs queued computations (yay first-class functions) in computational downtime.