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Frequent checks destroy a token bucket's fractional credit · case 02

The limiter admits too few or too many operations when fractional refills occur between requests.

Member previewVariant 2 · 3 implementations · 7 checks per implementation

Case contract

Capacity and initial balance are nonnegative integers with initial <= capacity; rate is nonnegative. Requests are [nondecreasing rational timestamp string,nonnegative integer cost]. Refill from time zero, cap at capacity, and accept iff sufficient credit exists. Return [acceptance flags,exact rational balance].

Why this case matters

Models token accounting under frequent polling without binary-float noise; timestamps are injected, so this experiment makes no claim about scheduler accuracy or concurrent atomic updates.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
fraction survives consumption	`[[true, false], "2"]`	`[[true, true], "0"]`	Failed

MEMBER ARCHIVE

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