My child won't stop eating!!! (Long)

I've been writing down how much DS eats for the past 2 weeks.  He eats on average 36oz/day (give or take one ounce depending on the day) but still - A LOT.  He also eats a full container of solids a day, as well as oatmeal or rice in the evening. Yesterday, we gave him a small bowl of prunes mixed with oatmeal for breakfast, a full container of carrots for dinner, and then some rice cereal before bed. This was on top of the 35oz he had consumed yesterday.  At bedtime, I gave him an 8oz bottle, and he looked like he could have actually had more, but I put him to bed.  He woke up at 12:45 (he hasn't woken up at that time since he was a newborn) for another 8oz bottle. DH fed him, and then said he ate the whole thing, and he went downstairs to get more, but by the time he got back, DS was asleep.  DS woke up at 6am for a 6oz bottle. So, basically, from 8pm - 6am he has consumed 22oz!! WTH!? We certainly feed him plenty during the day, so that can't be the issue.  Could he be going through an "out of cycle" growth spurt? Is this like sleep begets sleep but eating begets eating? (in terms of the solids).  I am so confused.  He is eating us out of house and home here

Granted, DH is a ginormous baby. He was 8.8 at birth and I weighed him on our infant scale yesterday and he's 17.2 (at 4.5 months) so he's more than double his birth weight. 

What can I do for him?! I feel bad that he's insatiable.  Also, he hasn't woken twice to eat at night for as long as I can remember - he typically STTN anywhere from 7-9hrs lately.  And he doesn't wake up at night for anything except to eat!