[CASSANDRA-12744] Randomness of stress distributions is not good

• Type: Bug
• Status: Resolved
• Priority: Low
• Resolution: Fixed
• Fix Version/s: 4.0-alpha1, 4.0
• Component/s: Legacy/Tools
• Labels: stress
• Severity: Low
• Assignee: Ben Slater
• Reporter: T Jake Luciani

Authors

Ben Slater

Reviewers

T Jake Luciani

• Created: 03/Oct/16 16:49
• Updated: 15/May/20 08:01
• Resolved: 06/Jun/17 13:43

Description

The randomness of our distributions is pretty bad. We are using the JDKRandomGenerator() but in testing of uniform(1..3) we see for 100 iterations it's only outputting 3. If you bump it to 10k it hits all 3 values.

I made a change to just use the default commons math random generator and now see all 3 values for n=10

Issue Links

• relates to: CASSANDRA-13940 Fix stress seed multiplier