git merge performance problem..

Junio, I think there is something wrong with git-merge. It sometimes takes up to ten seconds, and it's stuck at the

	git-show-branch --independent "$head" "$@"

call.

I don't know quite what that thing is even meant to do (we do already know the parents, why do we do something special here?) but even apart from that, the whole thing must be doing something seriously wrong, since it takes so long. Does it check the whole commit history?

		Linus