Kafka Partitions & Replication

Partitions provide parallelism; replicas provide failure tolerance#

A keyed producer selects a partition according to its partitioning strategy. Records in one partition have offsets and partition order; there is no total order across orders-0, orders-1, and orders-2.

Producer acknowledgement settings and the in-sync replication state affect latency and durability. Replication supports recovery subject to configuration; it is not an unconditional no-loss promise.