A priority queue is a container adaptor that provides constant time lookup of the largest (by default) element, at the expense of logarithmic insertion and extraction. - cppreference.com

See also

• Heap (data structure)
• Calendar Queues: A Fast O(1) Priority Queue Implementation (1998) - It is possible to make a calendar queue which will absolutely mop the floor with any other queue, but the algorithms given in these papers is just a starting point.
  • something like it already exists inside Linux. - The algorithm is something like the timer wheels in the Linux kernel.