In the talk "Beyond DevOps: How Netflix Bridges the Gap," around 29:10 Josh Evans mentions squeeze testing as something that can help them understand system drift. What is squeeze testing and how is it implemented?
It seems to be a term used by the folks at Netflix.
It is to run some tests/benchmarks to see changes in performance and calculate the breaking point of the application. Then see if that last change was inefficient or determine the recommended auto-scaling parameters before deploying it.
There is a little more information here and here:
One practice which isn’t yet widely adopted but is used consistently by our edge teams (who push most frequently) is automated squeeze testing. Once the canary has passed the functional and ACA analysis phases the production traffic is differentially steered at an increased rate against the canary, increasing in well-defined steps. As the request rate goes up key metrics are evaluated to determine effective carrying capacity; automatically determining if that capacity has decreased as part of the push.