I used OSB to sheet my shop, walls and ceiling. Its a bear to paint with a roller, you need to put the paint on heavy to get into the little divots. I tried a Wagner airless sprayer with the proper nozzle for latex. Worked great and used half the paint. Did it in two coats, some of the chips bleed into the paint, guessing heart wood. The first coat helps seal them, the second coat shows less bleeding but still some. A few years latter I had a wall cleared off when I was installing a car hoist, thought I'd freshen up the wall. That wall rolled on effortlessly and no more bleed. The ceiling was getting yellow from dust and fumes. Rolled it as well, again effortless once you get it sealed.
Greg