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Rate Limiter Comparison

Four algorithms on one burst pattern

Send the same traffic at a token bucket, a leaky bucket, a sliding-window log, and a sliding-window counter. Watch which requests they admit and which they drop. The algorithms disagree not about fairness in general, but about which customer gets hurt by a burst.

traffic pattern
rate (req/s)4
burst / capacity10
0s5s10s15s20s0246810state
admitted
62
rejected
33
admit rate
65.3%

Tokens accumulate at the configured rate up to the burst size. Each request consumes one. Idle time is banked; bursts are allowed up to what was saved.

The choice is never the cleanest algorithm — it is the shape of the traffic you actually see, and what kind of unfairness you can afford.

Rate Limiter Comparison — Internet Systems Labs · hbar.university