JCA connection manager ActiveCount

[jrwhitley]

I've been monitoring the number of Connections in the pool and it doesn't behave as I would expect. in that I  normally have a small number of connections actually in use (<5), the connections in the pool do not get removed as idle. This appears to be because the pooled connections are used in a round robin fashion and do not stay idle for long enough to meet the idle timeout I have set (10 minutes). Until I discovered this, I spent sometime looking for 'leaking' connections that were preventing connections being timed out of the pool.

Can someone confirm that this behaviour is to be expected?

[jesper.pedersen]

If you want to limit the active connections in the pool you can use the <capacity> element to specify the decrementer policy - you will want MinPoolSize - read more here http://www.ironjacamar.org/doc/userguide/1.2/en-US/html/ch05.html#deploying_capacity_policies

Then set <min-pool-size> to 0, <initial-pool-size> to whatever, <idle-timeout-minutes> to the interval you want, and you should be good to go.

HTH

[jrwhitley]

Jesper,

Thank you for your answer. I looked at the ironjacamar user guide and the use of MinPoolSize.

From the guide:

" The org.jboss.jca.core.connectionmanager.pool.capacity.MinPoolSizeDecrementer policy will decrement the pool to its min size for each request.

This policy is useful when you want to limit the number of connections after each idle timeout request. "

Can you explain what it means by a request in this context? Is it the next time an idle connection times out or simply the next time a connection is requested. If the latter, which connections are removed from the pool?

Thanks again

[jesper.pedersen]

The idle timeout request is defined by <idle-timeout-minutes> element - e.g. how often do you want to shrink your pool. In-use connections are never timed-out of course.

So, MinPoolSize is the most aggressive policy as it will remove all idle connections for each <idle-timeout-minutes> invocation.

HTH

[jesper.pedersen]

Well, depending on your settings of course. The Watermark policy is another option...