Even if you have a centralized source of truth, you might still have async updates.
For example, you have some beefy ‘central truth’ machines with 512GB of RAM. But you don’t want this client directly hitting this machine, so this machine pushes data out to “worker nodes”, which then pushes state out to clients.
Central Truth => many worker nodes
worker node => many clients
Here, each client is querying a different subset from the worker node.
Here, it is not unreasonable for the worker node to simultaneously read & write at the same time.
