Comment by bjackman

If your benchmarks are fast enough to run in pre-commit you might not need a time series analysis. Maybe you can just run an intensive A/B test between HEAD and HEAD^.

You can't just set a threshold coz your environment will drift but if you figure out the number of iterations needed to achieve statistical significance for the magnitude of changes you're trying to catch, then you might be able to just run a before/after then do a bootstrap [0] comparison to evaluate probability of a change.

[0] https://en.wikipedia.org/wiki/Bootstrapping_(statistics)