How does cloud elasticity differ from cloud scalability?

The distinction between cloud elasticity and cloud scalability is rooted in how resources are managed in response to varying workloads. Elasticity specifically allows for dynamic resource allocation, enabling systems to automatically adjust the number of resources provisioned based on current demands. This means that during times of high demand, additional resources can be seamlessly added, and during lower demand periods, those resources can be reduced, thereby optimizing costs and ensuring that performance levels are maintained without overprovisioning.

On the other hand, scalability refers to the system's ability to handle increasing workloads by providing the option to add resources (horizontal or vertical scaling) up to a predetermined maximum capacity. It doesn't necessarily involve automatic adjustment—scalable systems can accommodate growth but may do so through manual intervention or prior planning.

This understanding of how elasticity offers flexibility in resource use to meet real-time changes in workload, while scalability emphasizes the overall ability to handle growth up to a certain limit, clarifies the key differences between the two concepts.