Stimulus: A tester needs a large set of test data for system xyz.
Reaction: A specific generator creates 1GByte of test data for system xyz.
Metric: The data is created in less than 60 minutes
Background: The complex database structure of system xyz contains a few dozens of tables with around 100 columns and several dozens of (foreign-key) relationships/dependencies between these tables.
Data from production must only be used when heavily anonymized.