Workspace System Design
Learning pathsA
COURSE CHECKPOINT · 5 QUESTIONS

Quiz: Caching

Apply Caching 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.

Reader → Cache lookup (lookup); Cache lookup → Return cached value (hit); Cache lookup → Bounded loader (miss); Bounded loader → Source database (read); Source database → Versioned fill (value + version); Versioned fill → Cache lookup (populate)
Scroll to inspect the diagram, or open it at full size.

Figure — Reader → Cache lookup (lookup); Cache lookup → Return cached value (hit); Cache lookup → Bounded loader (miss); Bounded loader → Source database (read); Source database → Versioned fill (value + version); Versioned fill → Cache lookup (populate)

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.

A key expires during a database slowdown. Which matters more: adding cache clients or bounding cache-miss work?

1. A million clients miss one hot key together. What directly reduces duplicate fills?
2. A writer invalidates a key while an older read is still loading. What race remains?
3. May a cached in-stock value authorize the last item purchase?
4. What should happen when the cache fails?
5. Which key design risks leaking private data?

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