Alerts empowers developers to catch complications before they develop into problems, and helps you preserve high availability and deliver high quality of service.
It also assists you in making informed decisions about the present and the future, serves as input to automation of infrastructures and, most importantly, is an indispensable learning tool.
Alerts give you the opportunity to monitor the behaviour of your application processes and get notified when the threshold is violated.
Here we'll focus on the most important parts of an alert: Metric and Threshold.
Define what resource you want monitor and what metric of that resource. You can monitor the occurrence (count), the execution time or the memory consume.
Threshold represents when you want receive an alert. Different conditions allows you to detect different anomalous behaviours. For any type of threshold you can read a short descrition of their tipical use case.