Track 1 · Interview Foundations
Capacity Estimation and System Sizing
How to size servers, storage, databases, and caches in five minutes. Stating your assumptions, calculating peak QPS, and defending your architecture with simple arithmetic.
Guide20 min read
On this page
- The cluster that was sized for the wrong hour
- The core concept: order of magnitude, not school math
- Plain terminology for freshers and senior engineers
- Numbers every engineer should carry in their head
- The 5-step estimation funnel framework
- Real-world case study walkthroughs
- Decision matrix: what each number tells you to build
- Rules that keep your estimates honest
- Common interview cross-questions