I am confused about "log file flush". In my naive understanding, once
a message is produced and sent to the kafka server, it will be written
to the hard drive at the log file. Since it is in the hard drive
already, what exactly do you mean by "log file flush"?
I asked because we found that if we manually kill the zookeeper and
kafka server processes, the messages stored in the log file will be
lost. Is this expected behavior? Is there any setting to allow us keep
all the existing messages once they are written to the log file?