Hibernate 6 JPA performance degradation

[theigl]

I have reported query performance regressions in Hibernate 6 here:

Query performance regressions in Hibernate 6

I originally reported my findings as HHH-15854. Since reporting the issue, major performance improvements have been made and of the 4 test-cases attached to the ticket, 3 are now faster in v6. However, one of the tests is still significantly slower and seems to have major performance implications in our application: 5.6 Main Fetch Entities with Associations 38.74S 41.60S Fetch Entities without Associations 23.41S 22.82S Small Transactions Criteria 1M5.81S 56.42S Small Transactio…

And there is a corresponding Jira Ticket:

https://hibernate.atlassian.net/browse/HHH-17030

I don’t know if your issue has a similar root cause, but the best thing you can do is to create a reproducer for your issues.

Take a look at the JMH tests I wrote to demonstrate the performance regressions I’m facing.