The database is MS SQL Server 2000. We simulate 100 users to access our thin-client J2EE application, but some operations failed because no database connection can be obtained from the connection pool.
We find that we have to set
max-pool-sizeto 800 to pass the test.
Have you checked this wiki page?
http://www.jboss.org/wiki/Wiki.jsp?page=WhatDoesTheMessageNoManagedConnectionsAvailableMean