hi, no peopole would answer my question :(, mabye i didn't show the detail.

now, i show the detail code , hope to get some advice.
There are not more than 100 records in the db2 8.1.
I also find it spend more time to save a object at 2.11.

for (int i = 0; i < arg.length; i++) {
daoSupport.queryList("user.findby.name",
new Object[] {arg[i] });
}



public List queryList(String queryName, Object[] args)
throws DAOException {
Tools.argumentCheck(queryName, "query name");

Session session = null;

try {
session = openSession();

Query query = session.getNamedQuery(queryName);
setParameter(query, args);

return query.list();
} catch (HibernateException e) {
handelException("During query", e);
} finally {
releaseSession(session);
}

return null;
}

the length of arg array is 100, and only the query can get some records.

2.11 20*1000ms
2.03 500 ms

i modify the argument array, let every time can got the same record . the below is result.
2.11 20*1000ms
2.03 5000 ms

what happen? i aslo find it spent more time to save a object if i use the transaction.

2.1 dropped support for a prepared statement cache for internal database pool. If you are using the hibernate pool then setup one of the other database pools (such as C3PO) and try it again.

thx ,david, I have find this change at changelog of 2.10 beta4.