Glossary

Consumer poll loop (Kafka)

The Kafka consumer poll loop is the central control loop: call `consumer.poll(duration)` to fetch a batch of records, process them, then call `poll()` again. The poll call fetches records and sends heartbeats to the group coordinator. If `poll()` is not called within `max.poll.interval.ms`, the broker assumes the consumer has died and triggers a rebalance.

Formula: processingTimeMs × maxPollRecords must stay < max.poll.interval.ms or the consumer is evicted.

Last updated: March 2026