Scaling

Scaling refers to the transformation that either increases or decreases the units of resources used to serve requests from users. Scaling can be automatic or manual. Manual scaling requires an administrator to manually initiate the scaling process, while automatic scaling refers to an automatic increase or decrease in resources based on events available from the environment and ecosystem, such as memory and CPU availability. Scaling can be effected up or down, or out and in, which will be explained later in this section.