wiki/observability.md

Observability

Logs

• Unify code to log - configure to include module name: https://hexdocs.pm/logger/Logger.html
• Failures
• Audit logs

Metrics

• Take time to calculate - they aren't free

• Measure time

• If something happens: do the metrics reflect the state you envisioned?

  • Yes: good
  • No: bad metric

• Types of metrics

  • Business
    • Sales
    • Marketing
  • System
    • CPU
    • RAM
    • Process count
    • Performance
    • Availability
    • ...
  • Product

• Metrics kinds

  • Leading (short time): test hypothesis
  • Lagging (long time): whether actions were successful

Alarms

https://www.erlang.org/doc/apps/sasl/alarm_handler.html