CPU throttling under load
An image-thumbnailing service (Go) runs on Kubernetes. After a routine traffic increase (a marketing push doubled uploads), p99 latency degraded badly and requests started timing out, but per-pod CPU utilization shown in your dashboard reads only ~55% — nowhere near 100%. The HPA isn't scaling up because it's targeting 70% CPU and 55 < 70. The pod has `resources.limits.cpu: 1` and `requests.cpu: 0.5`. The container metric `container_cpu_cfs_throttled_periods` is high and rising. Triage and mitigate.
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.
0:00 of about 30 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.
Run or narrate your approach, then ask the coach.