Re: [c3p0-users] Connections not closed after calling close()

[Sean R. <sea...@ne...>]

It seems as though there is a race-condition in the somewhere in the shutdown logic of BasicResourcePool.  I added code to my application to search for the "Resource Destroyer in BasicResourcePool.close()" thread and wait until it completes.  However, intermittently, the pool will acquire another connection after I have shut down the pool and the resource destroyer thread has completed.  I added logging statements to the JDBC driver which logged the stack trace of the offending connection and I am certain it is from C3P0.  I am intermittently seeing the following stack trace *after* the resource destroyer thread has exited.

java.lang.Exception: Stack trace
	at java.lang.Thread.dumpStack(Thread.java:1206)
	at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:51)
	at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:182)
	at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:119)
	at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:143)
	at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:132)
	at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)
	at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)
	at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)
	at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)
	at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

BTW, I have also tried using the ScatterAcquireTask, and it did not resolve my problem.

The reason I need to make absolutely sure all connections are closed is because I am trying to drop the database and it fails if there are any other connections open to the database.  I would greatly appreciate anyone's help in trying to diagnose the race-condition.

Thanks!

________________________________________
From: c3p...@li... [mailto:c3p...@li...] On Behalf Of Sean Rohead
Sent: Friday, March 21, 2008 1:30 PM
To: c3p...@li...
Subject: [c3p0-users] Connections not closed after calling close()

I am using a ComboPooledDataSource with a minimum pool size of 1.  I am calling DataSources.destroy(dataSource) to close the pool.  However, after this call returns, there is still an active connection to the database.  It appears that the connections in the pool are not closed when the pool is closed (at least not synchronously).  How can I force the pool to immediately close all connections to the database or block until they have all been closed?

Thanks!