Far as I know, it counts clones etc, but have a cap each turn. As a wind user, my clones die all the time, feeding it.
But even in matches where both side have clones, I have yet to get to use more than 150 chakara in round 2 (btw I have sage naruto in team, so it's 40+20+90), I know as I run the dance mystery, my sage naruto and GNW kankuro can both cast once, then sage a second time after dance, never had enough chakra for second cast of kankuro, stop at 30 at most.
The limit appears to differ in 3v3, however, I think in group instance I've managed 2x2 cast before. I'm not 100% sure.