[deepu_256]

I guess what he means is that for drivers like mysql which are blocking only there is little support in tornado to not freeze the tornado instance during the request response cycle.

[inportb]

If you do use mysql, you're in luck... here's a pure python client module that can easily be monkey-patched for gevent/eventlet:

http://code.google.com/p/pymysql/

[j2labs]

That is correct. Eventlet has database pooling for python drivers that are written in C.

See my response to your other comment for how eventlet handles drivers written entirely in Python. In short, it converts them.