PrincipalPerformance & Load Testing
How would you design a performance testing strategy for a global application?
- global
- multi-region
- CDN
- distributed testing
Answer it first, then compare. Nothing here is saved or scored.
Model answer
Components: (1) Multi-region load generation: run tests from each region where users are. (2) CDN and edge caching validation: verify content is served from local edge nodes. (3) Database replication lag: measure read consistency across regions. (4) DNS and routing performance: test failover between regions. (5) User journey testing from each region: account for network latency in SLAs. (6) Time-zone-based load patterns: simulate realistic global traffic distribution. (7) Compliance: data residency requirements may affect architecture and performance. Infrastructure: distributed k6 agents, cloud-based load generation (k6 Cloud, Flood.io).
What interviewers listen for
- Workload modellingYou design the load shape from product traffic, not from tool defaults.
- Percentile literacyYou read p50/p95/p99 separately and explain why each matters.
- Bottleneck triageYou correlate metrics across application, database, and infrastructure layers.
- Capacity instinctsYou can translate a soak test into a sizing or scaling recommendation.