Two flags of rq_no_delay and rq_no_resend might not be necessary. We don't have precise definitions and uages conditions for them to distinguish them.

I think rq_no_delay means the request should quit and return whenever there is any possibility of being blocked, either it is caused by reconnection or other conditions. And rq_no_resend should always be set when rq_no_delay is set, which is true in a lot of places but not all. It is not clear why rq_no_resend is necessary. Even there is a case in which rq_no_delay is not suitable, a more precise flag or a better mechanism should be used.