Configuration.producerRequiredAcks

this field indicates how many acknowledgements the servers should receive before responding to the request if it is 0 the server will not send any response (this is the only case where the server will not reply to a request) if it is 1, the server will wait the data is written to the local log before sending a response if it is -1 the server will block until the message is committed by all in sync replicas before sending a response for any number > 1 the server will block waiting for this number of acknowledgements to occur (but the server will never wait for more acknowledgements than there are in-sync replicas)

struct Configuration
short producerRequiredAcks;

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