Connections not being released from jdbc pool on WLS 5.1 sp8

Question

I am using WLS 5.1 on RedHat Linux kernel 2.4
The database is oracle 8.1.6 and I am using the thin jdbc driver as shown in the config below.
weblogic.jdbc.connectionPool.bobePool=\
url=jdbc:oracle:thin:@localhost:1521:<sid>,\
driver=oracle.jdbc.driver.OracleDriver,\
loginDelaySecs=1,\
initialCapacity=10,\
maxCapacity=22,\
capacityIncrement=5,\
allowShrinking=true,\
shrinkPeriodMins=3,\
testConnsOnReserve=true,\
testTable=dual,\
refreshTestMinutes=5,\
props=user=<username>;password=<password>
The problem I am facing is that some connections remain active
after the SQL query has finished. The no. of open connections
keep on piling up till the limit of 18 connections is reached and
ultimately at that point weblogic hangs.
Has someone else faced this problem...and found a solution??
Regards,
Anish Srivastava
System Analyst
Baazee.com

Answer 1

Hi Caren,
Weblogic doesn't close connections on "time-out". There are some reasons
for this. The most important one is that even if you have such a
functionality,
in case of a connection leak all the available connections can be trashed in
a matter of milliseconds, so it wouldn't help at all. Though, weblogic does
close leaked connection when they are garbage collected, but it's easy to
see
that it doesn't help a lot, too.
So you need to make sure that all the JDBC objects are closed properly,
for example like in this code:
try {
} finally {
try {resultSet.close();} catch (SQLException se) {}
try {preparedStatement.close();} catch (SQLException se) {}
try {connection.close();} catch (SQLException se) {}
Also it's possible that you simply don't have enough connection.
You could try to increase size of the pool.
Regards,
Slava Imeshev
"Karen Law" <[email protected]> wrote in message
news:[email protected]...
Closing the DB connections is important. But is there any parameters to be
set in the WebLogic configuration in order to release the connection whenit
hasn't been closed for a long time? Say, setting the connection timeout?
Many thx!
Karen
"Deyan D. Bektchiev" <[email protected]> wrote in message
news:[email protected]...
Do you close the DB connections in a finally block after you've finished
using them?
If not your application is leaking the connections and sometimes GC is
not able or does not free those in a timely manner.
--dejan
Anish Srivastava wrote:
I am using WLS 5.1 on RedHat Linux kernel 2.4
The database is oracle 8.1.6 and I am using the thin jdbc driver as
shown
in the config below.
weblogic.jdbc.connectionPool.bobePool=\
url=jdbc:oracle:thin:@localhost:1521:<sid>,\
driver=oracle.jdbc.driver.OracleDriver,\
loginDelaySecs=1,\
initialCapacity=10,\
maxCapacity=22,\
capacityIncrement=5,\
allowShrinking=true,\
shrinkPeriodMins=3,\
testConnsOnReserve=true,\
testTable=dual,\
refreshTestMinutes=5,\
props=user=<username>;password=<password>
The problem I am facing is that some connections remain active
after the SQL query has finished. The no. of open connections
keep on piling up till the limit of 18 connections is reached and
ultimately at that point weblogic hangs.
Has someone else faced this problem...and found a solution??
Regards,
Anish Srivastava
System Analyst
Baazee.com