As we know, in the CAP theorem, "A" means "Availability". On wikipedia, the explanation of "Availability" is:
Availability: a guarantee that every request receives a response about whether it was successful or failed
However, from the perspective of engineering, there is no ABSOLUTE availability. We can only say that the availability of a system is 5'9'(99.999%), or even 8'9', but we cannot say that the availability of a system is 100%, 100% available system does not exit in reality, even if the system has millions of duplicated nodes, right?
The CAP theorem proves that no system could satisfy the 3 requirements simultaneously. My question is, if a system claims to satisfy both "A" and "P", what is the accurate meaning of this "A"? 6'9' or even higher?