Found "java.util.ConcurrentModificationException" in logs during test
During load test with 150 users on login logout flow of application , I found "java.util.ConcurrentModificationException" and 20% of vusers got failed to login into the system during this time.
Could anybody help on below:-
1. What this exception signified?
2. does it causes due to bad scenario designing.
3. It causes due to incapability of code to handle such concurrent load.
4. How I will be ensure , so that I could challenge development team to fix this issue.