Backpressure Mechanisms

Backpressure is the flow control mechanism that prevents a fast producer from overwhelming a slow consumer. Without it, queues grow unbounded, memory fills, and the system crashes. The interview tests whether you know multiple backpressure strategies and when each applies. Four Backpressure Strategies Kafka Consumer Lag: The Health Metric Consumer lag is the difference between the latest offset produced and the latest offset committed by the consumer. Growing lag means the consumer is falling behind. Stable lag means the consumer is keeping up. Shrinking lag means the consumer is catching up.