> You can just pass `--preload` to have gunicorn load the application once. If you're using a standard framework like Django or Flask and not doing anything obviously insane then this works really well and without much effort. Yeah I'm sure some dumb libraries do some dumb things, but that's on them, and you for using those libraries.
It's not always trivial to ensure none of your dependencies have import-time side effects. Sometimes the productivity/business benefit provided by the depedendency outweighs the pain introduced by the side effects.
If spinning up a few more workers will solve a performance problem for you, it’s probably worth the time to throw the preload flag on there and see what it does to your test suite. Since you are already cost optimizing at this point you probably have the time.
It's not always trivial to ensure none of your dependencies have import-time side effects. Sometimes the productivity/business benefit provided by the depedendency outweighs the pain introduced by the side effects.