A queue type that is bounded by time, rather than the number of entries, is useful

[dtaht]

One way to have a saner queue size for any kind of queue is to have one that is bounded by time to process the items, not by entries. Queues are either empty or full, otherwise, and there is no right magic number for "physical size" in any queue, at any workload.

Van Jacobson: http://www.pollere.net/Pdfdocs/QrantJul06.pdf

Ultimately I hope to write something codel-like for packet processing in rust but the general observation that queues should be bounded by time, holds.