Loading the challenge…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

Loading…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

Loading the challenge…

While this loads — quick one

Every subscriber must get each event. A queue, or pub/sub?

Message queueorPub/Sub

A queue hands each message to exactly one consumer — that is how work is shared out. Pub/sub copies every message to every subscriber.

API Rate Limiter — system design interview practice — PlayCloudLabs

System designfoundational

API Rate Limiter

A public API is being abused: a few clients fire thousands of requests a second and starve everyone else. The team wants to cap each client to a fixed number of requests per time window and reject the rest immediately, before any real work is done. The check has to be cheap, because it runs on every single request, and it has to be consistent across a fleet of identical API servers behind a load balancer, so a client cannot slip past simply by being routed to a different server each time. The limits themselves change rarely.

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Multiple choicePick the design from four
Fill the gapsComplete one drawn for you
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