Evaluation of the Typeahead Suggestion System’s Design

Requirements compliance

Evaluate the proposed design with short prefixes, hot terms, cold caches, an index rollout, and a failed serving node:

• Low latency: We minimize latency through several strategies:

  • Reduce tree depth to shorten traversal time.

  • Update the trie offline so write operations do not block the client's critical path.

  • Deploy geographically distributed servers to process requests closer to the user.

  • Use Redis as a caching layer over the database (e.g., Cassandra) for faster retrieval.

  • Partition tries to distribute load effectively.

• Fault tolerance: Route failed requests to ready replicas of a compatible snapshot. Detection and retry take time, so measure recovery latency. Partitioning alone does not provide another copy of a failed shard.

• Scalability: The architecture supports horizontal scaling. We can add servers or increase trie partitions as query volume grows.

Non-Functional Requirements Compliance