Code Room
On-callHardoc-p054
Subject Incident responseLevel Senior~20 minCommon in Reliability & on-call interviewsIndustries Technology, Software development

Question

Under moderate load, your service stops responding — threads are all stuck waiting on a slow downstream call and the thread pool is exhausted. How do you respond?

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.

Diagram & narrate the incident
Loading whiteboard…
Run or narrate your approach, then ask the coach.