Don't Wait for the Crash to Check Monitoring: A Practical Methodology for Linux Performance Baselines and Anomaly Detection
Overview You’ve probably been here: woken up at 3 AM by a pager alert, scrambled to check Grafana, and found CPU usage spiked to 85%. You panic, investigate for half an hour, and finally realize — this database server runs a scheduled backup job every day from 2:50 to 3:10 AM. CPU is supposed to be at this level. What went wrong? You didn’t know what “normal” looks like for this machine....