Guardrails And Safety easy
Each user in your B2B product has a tokens-per-minute limit. One customer onboards 2,000 users who all run batch jobs at once, and other tenants start seeing slowdowns. What is missing?
- A A per-tenant token limit, so one customer's total usage cannot starve other tenants.
- B A lower per-user token limit, applied equally to every user across all tenants.
- C A per-IP request limit, since batch jobs usually come from a small set of servers.
- D An input classifier that detects batch-style prompts and rejects them before inference.
Answer: A. A per-tenant token limit, so one customer's total usage cannot starve other tenants.
Rate limits must apply **per user and per tenant**, because many compliant users can add up to one tenant that exhausts shared capacity. A per-tenant cap may throttle a large customer's legitimate burst, which is usually handled through plan tiers. Lowering every user's limit (B) punishes all tenants for one tenant's volume. Per-user limits alone are enough only when each tenant has very few users.
One system design question a day, with spaced repetition so the ones you miss come back.
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