Question about 4 1/2 solid eating habits

My son will be 5 months in a week and 1/2. For his 4 month check up the ped said go ahead and start him on food. he was in the 95th percentile for weight and 70th for height. *he was 9 15 when he was born*. I remember when he was just a newborn and I thought he was eating a lot of formula, the ped said "feed him until he is satisfied". Is that the same for when they are on solid foods as well? For dinner he will eat a jar of baby food (stage one) and I make a 6 oz bottle, use two ounces for cereal and he'll drink about 3 oz after he is done eating everything else. Is that alot? He eats it and has NOOO problem with his bowel movemnts. He poops more and it smells worse. Should I be feeding him less? for breakfast he'll eat a jar and a little cereal and I don't give him cereal or anything for lunch. what do you think? When is a good time to start stage 2?