Scalability Foundations

Scaling means handling more load without degrading performance. The two main levers are vertical (bigger machines) and horizontal (more machines).

Read vs Write

• Read-heavy (feeds, profiles): Cache aggressively, replicate reads.
• Write-heavy (analytics, logs): Batch, partition, use append-only storage.

Inline Check 1

For a social feed with 10x more reads than writes, what scaling strategy fits best?

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Inline Check 2

Why is horizontal scaling often preferred over vertical at large scale?