Queueing

Bounded Queues Turn Overload into an Explicit Admission Decision

A queue between a producer and a slower consumer can absorb a temporary rate mismatch. It cannot remove that mismatch. If arrivals continue faster than completions, every accepted item adds to outstanding work. An unbounded queue lets that state accumulate until some other resource becomes the effective limit, often memory or an external timeout. A bounded queue moves the limit into the interface itself. Once capacity is exhausted, admission has to produce an observable result: wait for space, reject new work, discard selected work, or redirect it elsewhere. The queue therefore becomes more than a storage structure. Its capacity and full-queue behavior define part of the system’s overload contract.