It’s Time for Some Queueing Theory
Another fun surprising result from queuing theory is that if you have a buffer of pending RPC's that have some deadline, it is better to service them in a "unfair" LIFO order, as opposed to a fairer FIFO order. [0] goes into more gory details.In the bank example from the article, LIFO would dramatically shorten the median wait time (~5 minutes), at the cost of really upsetting customers [1].  In the case of a support queue, where the waiters are blind to each other, this cost could be reconsidered ...[0] https://arxiv.org/pdf/1008.4895.pdf[1] from the article, "We really, really hate it when someone shows up after us but gets served before us.