What is the difference between Kafka and traditional message queues like RabbitMQ?
Answer
Kafka and RabbitMQ serve different use cases. Retention: Kafka retains messages for a configurable period (days/weeks) regardless of consumption — messages are replayable. RabbitMQ deletes messages after they are consumed. Throughput: Kafka handles millions of messages/second through sequential disk I/O and batching. RabbitMQ is optimized for lower throughput with complex routing. Consumer model: Kafka uses a pull model; RabbitMQ pushes messages to consumers. Ordering: Kafka guarantees ordering per partition. RabbitMQ guarantees ordering per queue with some exceptions. Use cases: Kafka excels for event streaming, log aggregation, and replay. RabbitMQ excels for task queues, complex routing (direct, topic, fanout exchanges), and RPC patterns. Scale: Kafka is designed for large-scale distributed streaming; RabbitMQ is simpler to operate at moderate scale.