Top 3 Cold start Interview Questions
Browse 3 real-world technical and behavioral interview questions about Cold start. Review scenarios, edge cases, and architectural best practices.
The recommender is good for users with history and useless for the ones who just signed up. What do you serve them?
Serve context instead of history: popularity conditioned on the country, device and referrer you already have, then re-rank on the first two clicks of the session with a model that needs no user identity. Reserve slots for exploration, and segment every offline metric by history length, because a metric averaged over users with history cannot see this cohort at all.
How would you autoscale a GPU inference service?
Scale on queue depth or in-flight concurrency rather than request rate, because a GPU replica that takes minutes to load weights cannot be added after the queue has already formed. Then decide deliberately how much warm capacity to keep, since that is what you are paying to avoid cold starts.
How do you handle cold start for a brand new user and a brand new item?
Fall back to content features and segment popularity while behavioural signal is absent, then blend towards collaborative scores as interactions accumulate. New items also need guaranteed exploration impressions, or the already-popular items take all the traffic and nothing can dislodge them.