Our environment has two production DNN servers, each one running around 75 Portals. One of these servers works great. However, since upgrading to DNN 8.0.3 the second server is painfully slow when in edit mode. I've used the DNN Glimpse module to look for the source of the problem, and it looks like on the slow server calls to the stored procedures GetModule, GetSharedModulesWithPortal, and GetSharedModulesByPortal all take over 500 ms each. As a result pages with 4 or 5 modules end up taking over 10 seconds to load. On the fast server calls to the same stored procedures take 2ms or less.

I've tried running the same queries by hand in SQL server management studio and they only take a few milliseconds, so I'm baffled as to why they would take so long when called by DNN. 

I've double-checked the performance and optimization settings and they're all the same between the two servers (I've tried with both memory and file caching providers with no change). Any help would be appreciated.