Media & Data
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Little’s Law

Relates the number of items in a system to arrival rate and waiting time.

Formula

L=λ WL = \lambda\,W

Variables

LAverage items in the system
λArrival rate
WAverage time in system

Example

5 requests/s × 0.2 s each → 1 request in the system on average

Did You Know?

Little’s Law holds for any stable queue, from web servers to supermarket checkout lines.

dataqueueingitperformance

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