Performance Anti-Patterns in Hibernate

Patrycja Wegrzynowicz
Snippets:

• "premature optimization is the root of all evil"
• "expect unexpected"...
• avoid temporary changes
• careful with Collections: inadequate collection mappings can impact resulting # of queries
• OneToMany on owning side: lots of unnecessary locking / querying
• bulk processing through Hibernate --> use database operations instead

Conclusion

• big data = big problems -- my addition: with hibernate :-)
  • standard mappings don't handle large datasets well
  • smart model, bulk processing, projections
• read the manual
  • hibernate docs
  • think of consequences
• hibernate
  • smart policies / data structures

Nothing was said of my personal performance finding with Hibernate: maximally use readonly access whenever possible. The support for 'dirty' objects adds a lot of performance overhead if some model-parts are readonly.