I don’t think parameter count is a good metric for how fast a model should run. You can benchmark both the cases independently and see if the result what you expected.
Take a batch, run through f (time it few times)
Do it for g, and you will get a rough estimate of the time taken for forward, backward cases.



 DDavid:

If there’s a way to save f(A) for all A in I , and I can only forward/backward propagate them, please let me know.


You can store the results as files and then have the dataloader load these instead of the images for g.