Performance

Scaling is the mechanism by which the number of Hardware or Software instances is increased or decreased. This can be done manually or automatically.

If the load increases, Performance can be retained by Scaling up.
If the load decreases cost can be reduced by Scaling down.

Whether a component can be Scaled depends on the behavior of the component: if the component has to be scaled more than twice if the load doubles, the component cannot be Scaled. The Big O Notation is a means of describing this behavior.

[[Scaling]] can be done Horizontally, Vertically, or both.