Partial update is not an improvement for latency in the way you're thinking about it. It's mostly an optimization for tillers so they don't have to rerender som

Partial update is not an improvement for latency in the way you're thinking about it. It's mostly an optimization for tillers so they don't have to rerender some parts. You seem to broadly misunderstand several parts of the modern display architecture -- the goal you insist any sane window system should provide hasn't been provided by any, including the X Window System.