Capacity Planning Overview
Capacity planning answers: “Do we have enough resources to handle the traffic we expect—and what happens when traffic grows or something fails?”
The goal is to stay ahead of demand with the right amount of headroom—not too much, not too little. Without it, you’re either over-provisioned (wasting money) or under-provisioned (one spike or failure away from an outage).
What This Section Covers
Section titled “What This Section Covers”- Workload and Modeling — Workload characterization (peak-to-average, online vs batch vs streaming), capacity modeling intuition (queueing, tail latency), and headroom taxonomy (N+1, failure-domain, surge).
- Planning and Operations — Scaling thresholds, headroom policies, autoscaling, forecasting, dependency and failure-domain capacity, multi-region, and operational processes (planning cycles, surge runbooks, post-incident capacity updates).
How It Connects
Section titled “How It Connects”- Load and Stress Testing — Provides the data that feeds capacity models and headroom decisions.
- Caching Strategies — Caching can dramatically change your capacity requirements.
- Infrastructure Metrics — Utilization and throughput metrics are the inputs for capacity planning.
- Availability and the Nines — Capacity failures directly impact availability.