7.3. Session performance considerations
This section includes guidance for developing and administering scalable, high-performance Web applications using WebSphere Application Server Session support.
7.3.1. Session size
Large session objects pose several problems for a Web application. If the site uses session caching, large sessions reduce the memory available in the WebSphere instance for other tasks, such as application execution.
For example, assume a given application stores 1 MB of information per user session object. If 100 users arrive over the course of 30 minutes, and the session timeout remains at 30 minutes, the WebSphere Application Server instance must allocate 100 MB just to accommodate the newly arrived users in the session ...