Reviewed by Aditya Kumar · Last reviewed 2026-03-24
**Why Cache**: Video metadata (title, duration, thumbnail) is read-heavy; DB would bottleneck at scale. **Design**: (1) Multi-tier—Redis/Memcached for hot keys; TTL 1-24h; (2) Cache-aside—check cache, on miss load from DB, populate; (3) Invalidation—on update, invalidate/update...
Why Cache: Video metadata (title, duration, thumbnail) is read-heavy; DB would bottleneck at scale.
Design: (1) Multi-tier—Redis/Memcached for hot keys; TTL 1-24h; (2) Cache-aside—check cache, on miss load from DB, populate; (3) Invalidation—on update, invalidate/update entry; (4) Warming—preload popular during low traffic; (5) Partition by content_id for Disney+ scale.
Cost: Reduces DB load; Redis cost vs. DB cost. Avoid cache stampede with locking or probabilistic early expiration.
Pro-Move: 'We use cache-aside with TTL; on metadata update we publish to Kafka and consumers invalidate. Hit rate 95%.'
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