On-callMediumoc-p002

Subject Mitigation vs rootcauseLevel Mid–Senior~20 minCommon in Reliability & on-call interviewsIndustries Technology

Question

The primary database is pinned at 100% CPU and queries are timing out, taking the app down with it. You could hunt for the offending query, or act now. What do you do?

What a strong answer looks like

Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.

Learn the concepts

Diagram & narrate the incident

Loading whiteboard…

Run or narrate your approach, then ask the coach.