1 min read
Caching
Cache-aside, TTL strategy, and the data you should never cache.
Cache-Aside Pattern
Application checks cache first, falls back to database, populates cache on miss.
TTL Strategy
Set TTLs based on data freshness requirements. User profiles: 5-15 min. Static config: 1 hour+.
Invalidation
Invalidate on write, not on read. Use cache tags for related data invalidation.
When Not to Cache
- Financial balances (always read from source of truth)
- Real-time inventory counts
- Data with strict consistency requirements
Redis Patterns
SET key value EX 300for simple TTL caching- Hash structures for object caching
- Sorted sets for leaderboards and rankings