Aikajono

Aikajono, literally "time queue" in Finnish, is a term used to describe a queue data structure or organizational concept in which elements are ordered by an associated time value. In this arrangement, the temporal attribute, such as a timestamp, determines the sequence of processing rather than the order of arrival. The concept is used in computing, information processing, and process scheduling to manage events, tasks, or records that must be handled according to time.

In practical terms, aikajono is implemented with a time-keyed priority queue or min-heap, where the smallest time value is removed first. This makes it suitable for discrete-event simulation, real-time systems, and log or event management, where the next item to execute is the one with the earliest timestamp. Typical operations include inserting an item with its time key and extracting the item with the minimum time.

Although the exact Finnish term may be encountered mainly in Finnish-language texts, English-language discussions describe the same concept as a time-ordered queue, temporal queue, or time-priority queue. It contrasts with standard first-in-first-out queues that ignore time metadata and with simple priority queues that may use non-time criteria.

See also: queue, priority queue, timestamp, discrete-event simulation, and event scheduling.