From IBM Redbooks, Techniques for managing large WebSphere Installations:

Redbook, published: Thu, 13 Mar 2008

– High availability manager and core groups
– Tuning recommendations
– Configuration best practices

As WebSphere Application Server installations grow to accommodate the growth of business processing, the question “How large can a WebSphere Application Server cell be?” is being asked more often.

If you ever find yourself in a large WebSphere installation, this Red book is for you. It’s also good if you ever want to know all the communication that goes on between the various components of a cluster.