> I am using the term "control plane" in the typical systems sense, where the control plane is not the performance critical data pipeline. The control plane by definition is outside the critical request path. Relative to the performance profile of the data plane, the control plane is not performance critical.

That doesn't make sense because you're talking about io-uring itself having separation between control and data, however it is is exclusively involved with the request path. It seems like you made this confusion with your first post, I'm just replying to what you wrote.