Thanks for your reply,
If you’re talking about the slices in the init, I think it’s juste a way to define my operators and doesn’t affect the calculus (but I may be wrong).
In the forward pass, it may slow down but I didn’t get problems with this part of the network.
I realy got problems with self.features3 and self.score_fr. They go, on CPU, from a couple of seconds to severals minutes.