What is 'Backpressure' in stream processing?

What is 'Backpressure' in stream processing?

Approach: Describe handling data influx when downstream is slow.

A mechanism where a downstream component signals the upstream producer to slow down because it cannot keep up with the rate of incoming data, preventing system crashes.

Follow-up: What happens in a system without backpressure?

Key concepts: buffer, throughput, system stability.