Being separate systems is fine as long as they can all calculate a number within the time it takes to make a cup of coffee. That's not hard if you actually make it a design goal.

I'm sorry that "prioritize it" isn't very helpful, but it's true. If the calculation takes longer than that, it's a management-induced problem.

If we're positing a system that can already do that, then you need to be more specific about the problem you're describing because it's not obvious.