How to Control the Variability of a Process in the Cloud

We run these tests on computers, and computers are non deterministic. And deciding if the performance changed or not has been a hard problem. So we've done a lot of work to control that variability as much as possible. But then even on top of that, even with things controlled as much as you can, there's still variability. Yet, when we started, we tried to start as simple as possible.