End users can create and run groovy scripts that do not close database transactions, causing them to leak. Over time this can exhaust the database connection pool and lead to Nexus instability.
We have an article outlining this and how to avoid.
- Nexus should provide some sort of built in protection against poorly written scripts leaking resources like database transactions.
- Very likely this is logging unclosed transactions at ERROR (e.g. when they're finally garbage collected)