This is a sessionized, in-depth version of a Drupal 8 article series posted on Acquia's blog over the past few months: https://www.acquia.com/about-us/team/james-meickle

We'll detail the following points:

• Contemporary monitoring tools and strategies in Symfony and Twig
• The components in Drupal 8 that can be monitored
• Building a performance-monitoring Drupal 8 module via dependency injection
• Monitoring a large-scale, heavily cached Drupal 8 environment