Question

A developer runs a product catalog service backed by Amazon RDS and uses Amazon ElastiCache for Redis with a lazy-loading (cache-aside) strategy. Users frequently report seeing outdated product prices for several minutes after an admin updates them in the database. The team needs to ensure the cache reflects price changes immediately after a database write, while keeping the cache populated. Which change best addresses this?

Accepted Answer

Add a write-through step so the application updates (or invalidates) the cache entry as part of every database write.

Answer

Increase the TTL on all cached items so entries stay in the cache longer and reduce database load.

Answer

Switch the ElastiCache cluster from Redis to Memcached to enable automatic cache invalidation on write.

Answer

Enable a larger node type for the ElastiCache cluster to increase read throughput and cache freshness.