Improve free-threading performance

[Sam Gross]

I’m a CPython core developer working on free-threading. Would the Django team be interested in reviewing patches aimed at improving Django's performance on free-threaded Python (e.g., 3.14t)?

For example, there are a few scaling bottlenecks caused by creating temporary Field instances, such as in rel_db_type(). This can lead to contention on the shared creation_counter and also invalidate CPython’s attribute lookup cache. I expect most of the patches to be fairly small.

For context, I’m using Zulip to identify and investigate these issues, and I’m also working to fix the underlying problems in CPython upstream where possible.