📨 Partitions & Offsets

The Anatomy of a Kafka Topic — and How to Choose Partition Counts

A Kafka topic is split into partitions — ordered, append-only logs. Each message gets an offset (sequence number) within its partition. Producers choose partitions by key hash (or round-robin). Consumer groups divide partitions among members — each partition is read by exactly one consumer.

📤 Producer: How Messages Land in Partitions

Partitions: 4

Routing:

Messages0

Keys Seen0

Hottest Partition—

Skew0%

👥 Consumer Groups: Partition Assignment

Each partition is assigned to exactly one consumer. More consumers than partitions = idle consumers.

Consumers: 2