Donald is our contact with Travis, so I've explicitly added him to this email.
To give some details: we get 25 concurrent jobs across all the various "official" Python projects on GitHub hosted under the Python, PyPA, and PyCA organizations (which is a substantial bump from what most projects get; see
https://travis-ci.com/plans to get an idea of what we're getting for free). CPython itself uses 3 of those with any single PR or merge into a branch (docs, Py_DEBUG, coverage).
Now normally this works out great for us since CPython is probably one of the more active projects that gets to use this increased budget, and so we typically take a chunk of the 25 concurrent builds happily and get our builds started very promptly. But at the sprints we ran up against cryptography and their crazy build needs:
https://travis-ci.org/pyca/cryptography . IOW having every major Python project using Travis' free service at once hit us hard.
As to whether we can get more of a budget for the sprints at PyCon US (or any other conference), I don't know. Maybe Donald could tell us more detail and/or find out if next year we can plan ahead to get a temp boost for the four days. Otherwise we're talking about making PyCA suffer year-round by having them have to get their own quota or something.