I want to process multiple clients concurrently, but within each client I want to process their requests serially.
Say there's client A, client B and server S; below is an example of the communication flow I'm after:
D | A --(Q1)-(Q3)-(Q4)----------------> S
a | A <----------------(R1)-(R3)-(R4)-- S
t | B --(Q2)--------------------------> S
a | B <--------------------------(R2)-- S
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