🔗 Correlation & Realism · Days 13–18
Day 18: Distributed / Multi-Region Load
Objective
Generate load from multiple injectors or locations.
Scenario
If your tool supports distributed mode, configure two or more injectors. If not, run two independent instances from different machines and aggregate results.
Metrics to Watch
When It Clicks
One load generator becomes the bottleneck before the app does.
Solution
In JMeter distributed mode: start jmeter-server on each remote injector machine, then run the controller with `-R injector1,injector2 -n -t test.jmx -l results.jtl`. Each injector runs all threads in the plan - so set each Thread Group to total_users / num_injectors. Monitor injector CPU with top or Task Manager; if any injector exceeds 80% CPU it is the bottleneck, not the app. In k6 Cloud or k6 OSS with multiple instances: aggregate results with a shared output target (InfluxDB or Prometheus remote write).
Reflection
Was the app the bottleneck, or was one injector maxed out?
Deliverable
A distributed load test setup or a plan for it.
⚠️ Never run load tests against infrastructure you do not own or have explicit written permission to test. Always use a dedicated test environment. Unauthorized load injection can cause outages, trigger legal liability, and violate terms of service.