MDB Pool & Thred pool configuration in Websphere Application Server 6

Question

I am using Websphere Application Server (WAS) 6.1

Can someone asist me to configure max MDB pool size & max thread pool size for that particular MDB ? I need to execute one MDB instance in one thread only, there will not be more than 1 execution at a time.

Answer 1

This seems like a poor idea for scalability. It seems better to handle the concurrency at the database level (or whatever transactional system the MDB is operating on).

If you really believe it is necessary, you can simulate a singleton MDB by setting the poolSize property to H1 ("hard" instance max of 1) for your EJB. This will cause the EJB container to create at most one instance of your EJB, which means each thread that would deliver a message to the MDB will block waiting for the instance to become available.

-Dcom.ibm.websphere.ejbcontainer.poolSize=YourApp#YourModule.jar#YourEJBName=H1

It is not possible to configure a per-MDB thread pool.

Answer 2

如果不需要并发处理（通常用于MDB），则可以限制此MDB在WAS中绑定的侦听器端口的maximum sessions数参数。