Netflix — Notes

Functional

• Catalog browse + search + per-row personalization.
• Trailers, art selection, dubs/subs.
• Playback with adaptive bitrate + DRM.
• Account, profiles, parental controls.
• Downloads for offline.

Non-functional

• 250M+ subscribers; ~15% of internet downstream at peak.
• p99 playback start < 1.5 s.
• 99.99% control plane availability.

Capacity

• 1 EB+ of video served / month.
• Catalog: tens of thousands of titles × many encodes.
• Per-title encode: 100s of CPU-hours.

Schema highlights

• titles(id, type, metadata, ladders[])
• viewing(profile_id, title_id, ts, position, device)
• embeddings(title_id, profile_id, vec)

Trade-offs

• Open Connect dramatically lowers cost; needs hardware deployment ops.
• Pre-encode everything: storage explodes (50–100× original) but huge runtime savings.
• All-in on AWS for control plane vs own metal for CDN: hybrid sweet spot.
• Heavy microservice mesh demands chaos engineering culture.

Refs

• Netflix Tech Blog (years of posts on Hystrix, EVCache, Eureka, Spinnaker, Open Connect, per-title).
• "Optimizing video QoE at Netflix" papers.
• ByteByteGo "Design Netflix", Alex Xu Vol 2.