Caching for the Service Layer
A service-layer cache sits between your handler and your database, trading stale data for latency. This video shows where the cache lives in the request path, how a cache key is built from request data, and what invalidation strategies actually do when the underlying data changes — including the stampede that happens when a hot key expires.
Topics covered:
- Where the cache sits in the request path
- Cache keys: what identifies a response and its dependencies
- TTLs and staleness: how fresh is fresh enough
- Invalidation: write-through, write-behind, delete-on-write
- Cache stampede: the thundering herd on a missed key
- Distributed caches: Redis, consistency, and network latency
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