Reaching nirvana

Now that we know how to add almost any metric to HPAs, they are much more useful than what it seemed in the Chapter 1, Autoscaling Deployments and StatefulSets Based on Resource Usage. Initially, HPAs weren't very practical since memory and CPU are, in many cases, insufficient for making decisions on whether to scale our Pods. We had to learn how to collect metrics (we used Prometheus Server for that), and how to instrument our applications to gain more detailed visibility. Custom Metrics was the missing piece of the puzzle. If we extend the "standard" metrics (CPU and memory) with the additional metrics we need (for example, Prometheus Adapter), we gain a potent process that will keep the number of replicas of our applications in sync with internal and external demands. Assuming that our applications are scalable, we can guarantee that they will...