🔗 Correlation & Realism · Days 13–18
Day 15: Realistic Data Feeds
Objective
Feed large and varied datasets; avoid data starvation.
Scenario
Create a data file with 1000+ rows of realistic values. Configure your script to cycle through them. Ensure no row is reused within a single test run.
Metrics to Watch
When It Clicks
Reusing the same 10 rows turns a load test into a cache test.
Solution
Generate a realistic dataset: export production search terms, user IDs, or product SKUs from your analytics tool (anonymized). In JMeter: CSV Data Set Config with 'Recycle on EOF = false' and 'Stop thread on EOF = true' if you want each row used exactly once, or 'Recycle = true' for continuous cycling. Set 'Sharing mode = All threads' only if the data is read-only. For 1000+ rows the file must be on the load injector's disk - not a network path. In k6 use SharedArray to load the file once across all VUs.
Reflection
How many unique data combinations does your production traffic actually use?
Deliverable
A script with a large parameterized data set.
⚠️ 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.