I question the relevance of these tests. With all the attention being given to performance, everyone seems to be overlooking the fact that Tornado provides zero support for truly asynchronous web applications written for it.

If you have any kind of long-running task to perform during a web request, you have to roll your own way of dealing with that task.

To make it worse, the demos included with tornado that make use of a relational database do all their queries in blocking fashion, which would render the server completely unusable during the runtime of every single query.

Given the fact that Twisted provides a robust API for dealing with long-running algorithms, as well as support for a huge number of other protocols, you're paying an awful lot for only slightly better performance.

In fact, in a real-world application, the performance benefit of Tornado is directly impacted by how good you are at dealing with asynchronicity.