Modeling performance based on scale requirements

For a software system, performance generally refers to the overall responsiveness of a system when executing an action within a specified time period, while scalability is the ability of the system to handle increased user loads without constraining the resources that may have an impact on the performance of the system.

A system is deemed as scalable if the underlying resources are made available dynamically to support the increase in load. Cloud applications must be designed for scale and the traffic volume is difficult to predict at times. There may be seasonal spikes impacting the scale requirements, especially in a multi-tenant kind of scenario, when the service may serve requests for multiple tenants.

So, it is a good practice to design applications in such a way that they can scale out automatically to meet the peaks in demand. Basically, the system should just scale up or down based on the load. Scalability concerns not...