Leaky bucket
(重定向自Leaky bucket algorithm)

The leaky bucket is an algorithm that may be used to determine whether some sequence of discrete events conforms to defined limits on their average and peak rate or frequency. It is based on an analogy of how a bucket with a leak will overflow if either the average rate at which water is poured in exceeds the rate at which the bucket leaks, or if more water than the capacity of the bucket is poured in all at once.