Scaling Reads hard
A user reads a comment they posted. They refresh the page, and the comment disappears (Time Travel). This happens because the second read hit a lagging replica. What consistency guarantee specifically prevents 'Time Travel' without requiring Strong Consistency?
- A Monotonic Reads
- B Atomic Broadcast
- C Causal Consistency
- D Serializable Snapshot Isolation
Answer: A. Monotonic Reads
Monotonic Reads guarantees that if a process has seen a particular value of an object, any subsequent reads will return that value or a newer one. It prevents the user from seeing data 'go backward' in time.
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