Prep RoomSign inStart free
Code RoomLatency spike root cause
HardPrep Room Coding #4188

Latency spike root cause

Vibe & agenticReliability & on-callSenior–Staff~20 min

Production alert: p99 latency on your Go search service tripled at 02:14 UTC and error rate is creeping. No human deployed anything overnight, but several AI-agent PRs auto-merged after passing CI. You need to trace the incident to a root-cause change fast. Walk me through how you go from 'latency tripled at 02:14' to the specific AI commit responsible, and how you confirm causation rather than coincidence before you revert.

Implement
find_suspect_deploy(deploy_minutes: list[int], deploy_shas: list[str], onset_minute: int, window_minutes: int) → str
Examples
in[[60,132,200],["a1","b2","c3"],134,30]out"b2"
in[[110,132,200],["a1","b2","c3"],134,30]out"ambiguous"
What a strong answer looks like

Treat the AI’s output as a draft to verify, not an answer to trust. Name the specific flaw and the input that triggers it, say how you’d catch it (tests, edge cases, reading critically), and how you’d re-prompt or decompose to get it right.

0:00 of about 20 min

Vibe & agentic: describe the solution in plain language (or narrate it) and the coach grades your approach.

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.