Burst and nodelay options in Nginx - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the burst option do in nginx rate limiting?

The burst option allows a temporary extra number of requests to pass beyond the set rate limit. It acts like a small buffer for sudden spikes in traffic.

beginner

Explain the nodelay option in nginx rate limiting.

The nodelay option lets requests in the burst queue pass immediately without delay. Without it, requests in the burst queue are delayed to match the rate limit.

intermediate

How do burst and nodelay work together in nginx?

The burst option allows extra requests to queue up temporarily. The nodelay option makes those queued requests pass instantly instead of waiting, helping handle sudden traffic bursts smoothly.

intermediate

What happens if you set burst without nodelay in nginx?

Requests above the rate limit are queued up to the burst size but are delayed to match the rate limit speed. This can cause some requests to wait before being processed.

beginner

Give a simple nginx configuration snippet using burst and nodelay.

limit_req_zone $binary_remote_addr zone=mylimit:10m rate=5r/s; server { location /api/ { limit_req zone=mylimit burst=10 nodelay; } }

What does the burst option control in nginx rate limiting?

A Timeout for requests

B Number of extra requests allowed temporarily beyond the rate limit

C Maximum number of concurrent connections

D Size of the request body

The burst option allows a temporary buffer of extra requests beyond the set rate limit.

What effect does the nodelay option have when used with burst?

A Allows burst requests to pass immediately without delay

B Delays all requests to match the rate limit

C Blocks burst requests

D Increases the rate limit permanently

nodelay makes burst requests pass instantly instead of waiting.

If burst is set to 5 and nodelay is not used, what happens to the 6th request arriving quickly?

A It is rejected immediately

B It passes instantly

C It is delayed to fit the rate limit

D It increases the burst size

Without nodelay, burst requests beyond the limit are delayed to match the rate.

Which directive defines the rate limit zone used with burst and nodelay?

A server_name

B limit_conn_zone

C proxy_pass

D limit_req_zone

limit_req_zone defines the shared memory zone and rate for limiting requests.

Why would you use burst and nodelay together?

A To allow sudden traffic spikes without delay

B To reject all extra requests

C To slow down all requests

D To increase server memory

Together they allow extra requests to pass immediately, handling traffic spikes smoothly.

Describe how the burst and nodelay options affect request handling in nginx rate limiting.

Think about how nginx handles sudden spikes in requests.

Write a simple nginx configuration snippet that limits requests to 10 per second with a burst of 20 and uses nodelay.

Use $binary_remote_addr for the zone key.