This should be called "not-as-blocking" MySQL queries. As they say in the blog post, the calls to send and read still block, but they've made it so you don't call read until there is at least something to read. I imagine this will be an improvement over many setups.

To add to the list of truly non-blocking MySQL libraries, check out Erlang's MySQL driver: https://github.com/Eonblast/Emysql