We have recently moved and partially enhanced an Oracle forms application to a Java based architecture using Hibernate on Jboss.

The amount of SQLs Hibernate is generating compared to its predecessor is significantly high and is causing CPU bottlenecks on the database server (Oracle 9i). This has raised a commerical issue as well, because if usage of Hibernate increases CPU utilisation on the DB server, it will be very expensive to add CPU capability to the DB server in light of the fact that the Oracle licence cost will increase as well.

Any inputs on how we can achieve better performance and scalability using some of the Hibernate settings / best practices will be appreciated.

Many Thanks!

We have experienced a similar issue in the past.
Ultimately we discovered that it was not at a problem with the Hibernate but the way we were using it .

Here are few key areas you can look at :

1)Its important that you identify which strategy best suits you application design – more precisely a usecase. I have seen people using session_per_operation model where they should be using session_per_request.

2)Its important that you track the sqls generated for each call and ask yourself whether or not you intend those. Maybe you have some problems in mappings(hbm) or design

3)Fetching Strtergies is one of the key things you need to understand properly and hence override the basic configuration whenever required, with proper use of HQL.

4)Make sure you are leveraging Hibernates secondary cache - and/or Query cache. This can benefit you the maximum if you use it properly.

5)Though Hibernate does have support for bulk/batch operations – but you can still consider direct jdbc where you have intense reporting etc.

Net-Net – Hibernate can be your best friend if used properly but believe me it can screw your application if you ignore some basic rules.

Hope this helps you!

This has to done on case by case basis .. there is no
magic "generate_less_sql" switch which would solve your problems

Thanks Monu.

Scarface - Case to case yes, but what do we look for was the question.

I did expect it to be something other people would have come across and hence decided to gain from their experience.

hi i'm new on hibernate and need to use mysql and maxdb and i can't configure hibernate.cfg.xml can u help me ???
oNE OF THE EXCEPTIONS I HAVE IS:

1:15:21,306 FATAL DriverManagerConnectionProvider:65 - JDBC Driver class not found: com.sapdb.jdbc.DriverSapDB
java.lang.ClassNotFoundException: com.sapdb.jdbc.DriverSapDB
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unk

REALLY 10X