Workspace System Design
Learning pathsA
COURSE CHECKPOINT · 5 QUESTIONS

Quiz: Dealing with Contention

Apply Dealing with Contention to concrete decisions. Choose an answer for every question, then review the explanations.

Visual checkpoint

Use this diagram to locate the state and failure boundaries tested by the questions. Answer all five questions before revealing feedback; the result is a study checkpoint rather than a certification.

Concurrent callers → Atomic state owner (conditional change); Atomic state owner → Winner (predicate matches); Atomic state owner → Conflict response (predicate fails); Lease epoch → Fenced destination (current token); Winner → Fenced destination (authorized effect)
Scroll to inspect the diagram, or open it at full size.

Figure — Concurrent callers → Atomic state owner (conditional change); Atomic state owner → Winner (predicate matches); Atomic state owner → Conflict response (predicate fails); Lease epoch → Fenced destination (current token); Winner → Fenced destination (authorized effect)

Review your reasoning

After checking answers, identify the incorrect assumption behind each missed question. Rewrite it as a rule with a concrete exception or failure case, then return to the lesson.

Why does adding a distributed lock with a 30-second expiry not guarantee only one worker writes a result?

1. Why can read-then-write oversell even with a fresh read?
2. An optimistic update affects zero rows. What does that commonly mean?
3. Why is a lease alone insufficient to reject an old worker?
4. What usually reduces lock contention?
5. Where must fencing be enforced?

Answers and your latest score are saved to your account when you check them. Completion records your attempt, not a passing certification.