The convoy phenomenon
Mike Blasgen, Jim Gray, M. F. Mitoma, Tom Price · ACM SIGOPS Operating Systems Review · 1979
When driving on a two-lane road with no passing one often encounters clusters of cars.This is because a fast-moving car will soon bump into a slow one.The equilibrium state of such a system is for everyone to be in a convoy behind the slowest car.In System R [Astrahan], transactions often bump into one another when contending for shared resources.This contention appears as conflicting requests for locks.(You may know locks by the names semaphore, monitor, latch or queue.)Typically, access to these resources follows the protocol: