Scalability and Load Testing Questions

Designing, executing, and interpreting performance and scalability tests for systems that must handle high traffic and large data volumes. Topics include creating realistic user and traffic patterns, ramp up strategies, steady state and stress scenarios, endurance and spike testing, and methods to identify breaking points, failure modes, and nonlinear bottlenecks. Covers test types such as load testing, stress testing, performance testing, chaos engineering, and multi region testing under degraded network and failure conditions, as well as testing with realistic data volumes. Emphasizes instrumentation and observability best practices, including which metrics to collect such as latency percentiles, throughput, error rates, and resource utilization, and how to interpret those metrics to find bottlenecks and derive capacity plans and autoscaling policies. Discusses graceful degradation and fault tolerance strategies, fault injection and chaos experiments, test automation and orchestration, test environment fidelity and realistic data generation or masking, avoiding false positives from unrealistic setups, and identifying and removing performance bottlenecks in the test harness itself. Includes practical considerations for optimizing test execution for cost and speed and using test outcomes to inform system design, operational runbooks, and production readiness.