We have a small installation (100 users) but we have a lot of email. Right now we have 1.5 million emails in our system and these are "active" emails, not junk.

The structure of our email system is centered around several email resources or "repositories" that house the bulk of our email so that it can be shared with the entire organization. (Like centrally located file cabinets.) Lately we have had some noticeable performance degradation.

I am looking for suggestions on how to improve performance. My initial ideas is to break up the single GW server into 3 servers: POA, Quicksearch (POA),GWIA (everything else)

What are your suggestions?