I currently have the WordPress MU Domain Mapping plugin installed and it's working fine. The front end of my sites load alright but the backend dashboard is incredibly slow.
I installed the Go Daddy P3 - Plugin Performance Profiler to see if that could give me some insight and I found that the WordPress MU Domain Mapping plugin was causing around an extra 20 seconds of load time only when it tried to load anything under /wp-admin/
I am currently on a VPS with IIS installed.
Does anyone have any suggestions?