You learned about autoscaling in Chapter 4, Principles of Solution Architecture Design. You learned about predictive autoscaling and reactive autoscaling in the section titled Design for scale. The concept of autoscaling became popular with the agility provided by the cloud computing platform. Cloud infrastructure allows you to easily scale up or scale down your server fleet based on user or resource demand.
With a public cloud platform such as AWS, you can apply autoscaling at every layer of your architecture. In the presentation layer, you can scale the web server fleet based on your requests, and at the application layer based on the server's memory and CPU utilization. You can also perform scheduled scaling if you know the traffic pattern when the server load is going to increase. At the database level, autoscaling is available for relational databases such as Amazon Aurora Serverless and the Microsoft Azure SQL database. A NoSQL database such as Amazon DynamoDB...