Glossary

Backpressure

Letting a slow consumer signal upstream to slow down, instead of being overwhelmed and dropping data.

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Definition

Letting a slow consumer signal upstream to slow down, instead of being overwhelmed and dropping data.

How it works

Without it, a fast producer floods a slow consumer until queues blow up memory or messages are lost. Bounded queues, blocking writes, credit-based flow control and load shedding (rejecting early with 429) all push the pressure back to the source so the system degrades gracefully.

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Common questions

What is Backpressure?

Letting a slow consumer signal upstream to slow down, instead of being overwhelmed and dropping data.

How does Backpressure work?

Without it, a fast producer floods a slow consumer until queues blow up memory or messages are lost. Bounded queues, blocking writes, credit-based flow control and load shedding (rejecting early with 429) all push the pressure back to the source so the system degrades gracefully.

What is Backpressure used for in system design?

Without it, a fast producer floods a slow consumer until queues blow up memory or messages are lost. Bounded queues, blocking writes, credit-based flow control and load shedding (rejecting early with 429) all push the pressure back to the source so the system degrades gracefully.

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