The autoscaling design pattern typically refers to the ability to auto-scale processing and storage capacity, both by increasing and decreasing assets. This is one of the greatest benefits of using a cloud-based Infrastructure as a Service (IaaS). The concept is simply that when you need additional capacity, your system is automatically scaled. Using the autoscaling reactive design pattern, our systems can automatically react to increases and decreases of system events such as increased or decreased web page visits, number of transactions, larger datasets, and so on.
As an example, we might have designed an online store with the ability to support 100 simultaneous potential customers. What if, during the holiday season, we receive 1,000 simultaneous users all querying our product catalog and processing orders? Our system might not be...