What is Liveness?

As it relates to concurrent computing, liveness refers to an application's ability to execute in a timely manner, so that a distributed system is able to continually execute computations. This property allows a system to make progress despite the fact that its computational processes may need to take turns to be completed correctly instead of being carried out in a simultaneous manner. The opposite of liveness is idle, meaning that a system is unable to perform computations quick enough for the system to operate optimally.