MQTT: Mosquitto broker queue test

Hi Stephen,

If you want to take a look and compare, I wrote some code to test_client.py and also a mqtt_pubsub.py wrapper in order to include MQTT protocol to the comparison you made. It is meant to be used with Mosquitto broker.

I run a test on a Ubuntu 12.04 64 bits, Intel Core2quad Q9550. Everything installed as your Readme suggests, Redis and Mosquitto from official Ubuntu repository with default configuration. My results point out that ZeroMQ is still quicker and that it takes advantage (like redis) from multiple core while Mosquitto is still quicker than Redis its results clearly shows that broker is not multi-core aware. I will run this on another machine, a Phenon X4/X6 to have something to compare with.

Anyway, I had not so experienced with python and if someone finds any issue with mqtt_pubsub.py I will gladly merge corrections. I have no experience with Go language so I still did not write any Go client to Mosquitto.

Thanks for your work, I would not get so far without your original code. This study will be decisive in a research I am conducting here.

Regards,
Benito.