KloudBuster is tool to load OpenStack clouds end to end, control plane and data plane and "all batteries included". It distinguishes from other open source scaling tools (such as OpenStack Rally, IBM CloudBench) in the following points:
KloudBuster tries to do one thing well and only one thing (and that is scale testing of the control plane and data plane in very specific conditions);
It does not try to be super flexible in allowing users to write their own scenarios using python or any other language and it is not a test development framework with APIs that developers can use to develop custom use cases;
It strives to be very simple to use and to "just work" despite providing a way to generate consistently massive load on any cloud size

For general Q&A use: https://gitter.im/kloudbuster/general