If you want him to grow faster you can feed him more. I've been feeding my reticulated python medium rats that leave a big bump followed by several adult mice, all in one feeding. And have been feeding twice a week. She has grown almost half a pound in two weeks! A small rat that doesn't even leave a bump every two weeks would result in super slow growth (if that's what you want). I've heard that with snakes you can pretty much control to rate of growth 100% because they almost always will eat twice a week if you offer it to them. On the other hand I got a free ball python that was fed a fuzzy mouse once a month. He was a year old and looked like he was only a month old WOW. When I first got him he ate three adult mice in about an hour LOL. Now I feed him one or two rodents twice a week and he is growing like a weed.........
Here's an example of how large of a meal you can feed your snake. I would never suggest feeding live like this video, just way too risky for the snake, better to feed fresh killed or frozen thawed. But you get the idea of how large of a rodent you can feed in comparison to the size of the snake: