Backpressure

Definitions

1. A flow control mechanism where a slow consumer signals an upstream producer to slow down, preventing buffer overflow and memory exhaustion. Without backpressure, a fast producer overwhelms a slow consumer, leading to dropped messages or OOM. Implemented in Reactive Streams, TCP (window size), Kafka (consumer lag), and Node.js streams.

   In plain English: A way for a slow system to tell a fast system 'slow down, I can't keep up,' preventing overload.

   Example: "The Kafka consumer is lagging -- backpressure via consumer group pause prevents the message broker from filling memory with unprocessed messages."

Related Terms

• Webhook vs. Polling
• Event-Driven Architecture
• Circuit Breaker
• Backoff
• Load Shedding
• Windowing
• Watermark
• Consumer Group