A client is requesting a special web application topology that seems odd to me. In a mid-sized SP2010 farm (two WFEs, two app servers) they will have hundreds of site collections. The requirement is to distribute them among multiple web applications because of expected better utilization of server resources, especially memory.
I'm not aware of such a method to gain better hardware utilization and increase performance. Also, I can't think of a simple way to make all these web apps accessible from a single hostname and port — except using URL mapping on some application proxy like TMG and hence increasing the administration overhead. Also, all site collections will have the same authentication settings and will use the same set of services.
- What are the pros and cons of distributing site collections among multiple web apps just for the sake of performance and/or WFE hardware utilization?
- Would it lead to a performance gain or loss?