[GERONIMO-4993] Requests for db pool resources will exceed Max Pool Size when EJBNetworkService beans are all busy

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.3, 2.2
• Fix Version/s: 2.1.5
• Security Level: public (Regular issues)

Environment

Linux and Windows XP

• Assignee: David Jencks
• Reporter: Eric Phetteplace
• Created: 19/Dec/09 18:22
• Updated: 02/May/13 02:29
• Resolved: 19/Mar/10 02:33

Description

In production, I have 100 EJBNetworkService threads. It works OK until there's a spike in traffic and all the threads are being used, and the 40 "max pool size" is ignored, and Geronimo makes 100's of DB connections.

In production, I am using an Oracle DB pool, so the DBAs aren't happy when my servers use up all the available server connections.

To recreate:

1. Change config.xml and start Geronimo:
<module name="org.apache.geronimo.configs/openejb/2.2-SNAPSHOT/car">
<gbean name="EJBNetworkService">
<attribute name="port">${OpenEJBPort + PortOffset}</attribute>
<attribute name="host">${ServerHostname}</attribute>
<attribute name="multicastHost">${MulticastDiscoveryAddress}</attribute>
<attribute name="multicastPort">${MulticastDiscoveryPort}</attribute>
<attribute name="clusterName">${ClusterName}</attribute>
<attribute name="threads">5</attribute>
</gbean>

2. Reconfigure the jdbc/ArchiveDS DB Pool:
Max Pool Size: 3
Blocking Timeout: 1000
Idle Timeout: 1

3. Install WAR
4. In web browser, go to http://localhost:8080/PoolTest/PoolTest. Reload it 5 times. Take your time It should be fine, and will give you an error when the pool is maxed.
5. In JMX Viewer, go to Geronimo MBeans, JCAConnectionManager, and pull up jdbc/ArchiveDS. Note the connection count. Looks good.
6. Wait for the connection count to return to 0.
7. In your browser, hold down F5 so the page reloads many times.
8. Observe the connection count again. It will be over connections.
9. If you repeat 6-9 you can easily get > 20 connections. I just held F5 for 6 seconds and there are 60 connections.

I will attach WAR (I don't see an option on this screen).

Issue Links

• depends upon: GERONIMO-5150 Connection pool idleReleaser should not expand the number of permits