Websphere/Oracle 11 - much more Heap Usage than with Oracle 10

Question

Hi all,
while testing our application with Oracle 11 (previously, we had Oracle 10), we saw that our server uses much more heap space.
It seems as it has something to do with T4CConnection/T4CPreparedStatement; there are 500 objects of T4CPreparedStatement allocated. Someone told me, that Oracle 11 is using SoftReferences to keep the connection pool; but we don't need that.
Is that correct? Could that be the problem for the increased heap space? If yes - how can we avoid connection pooling?
Thanks a lot!!
Edited by: 840550 on 28.02.2011 23:37

Answer 1

I suspect you are getting a connection for each user and holding onto it for the duration that he is logged in. Also, that you are not closing resultSet and preparedStatements correctly. Rewrite all your code to get/use/close a connection each time its needed as quickly as possible in a try/catch/finally block. There is no performance penalty opening and closing connections countless times in your code (actually, you are not really closing it, but returning it to the pool).
Here is a previous post I provided on how to get/use/close a connection:
Re: can not get the right query result using JDBC
Note: within the above example, you can pass the already open connection to another function within the above function for it to use. Within that other function, you create a new preparedStatement and resultSet. After using it, you close the resultSet and preparedStatement (in that second function), but not the connection (its closed in the outer function).