Talking about round-robin, I am reminded of the elevators at the block of flats where I live.
I've been frustrated at the elevators before. Sometimes when I call for
the elevator, I can tell that 2 of the lifts are in transit (going
somewhere, with or without passangers).
Sometimes only 1 out of 3 is in
When I call the lifts, I expect one of the lifts that are
parked to be mobilised. Instead, the logic that drives the lifts
assignment lets that lift go in the opposite direction, then come to a
rest, (either to drop off some passenger or park itself), then wakes
itself again, to come to my level. There are many other cases of
combination of the lifts doing different things mid-way, and reacted in a
very inefficient manner, resulting in my having to wait a huge amount
of time before a lift picks me up. Now I realise this has totally got to
do with the concept of round-robin (or the lack of) assignment.
They may be using another set of rules to guide the scheduling algorithm on which lifts to activate for all I know. Maybe I should go and read up a bit of elevator scheduling just to clear my doubts. :)