Backpressure
ELI5 — The Vibe Check
Backpressure is when a slow consumer tells a fast producer to chill out. If your database can only handle 100 writes/second but your queue is pushing 1,000, backpressure signals the queue to slow down. Without it, you'd buffer until you run out of memory and crash.
Real Talk
Backpressure is a flow control mechanism in streaming and distributed systems where downstream components signal upstream components to reduce their output rate. It prevents resource exhaustion from unbounded buffering. Implemented through reactive streams (RxJS, Project Reactor), TCP window sizing, message broker acknowledgments, or explicit pause/resume signals.
When You'll Hear This
"The Kafka consumer applies backpressure when the processing pipeline falls behind." / "Without backpressure, our ingestion pipeline OOM'd during traffic spikes."
Related Terms
Load Shedding
Load shedding is intentionally dropping some requests when your server is overwhelmed so it can keep serving the rest.
Message Queue
A Message Queue is a waiting room for tasks. Producers drop tasks in the queue, consumers pick them up and process them one at a time.
Streaming
Streaming is when the AI sends you its response word by word as it generates, instead of making you wait for the whole thing at once.