Improving the Performance of a NAS Solution

I need help with a NAS solution we're testing. We created a search-engine application that retrieves search results from an inhouse database. Microsoft IIS then pools the results and delivers them to the client via the Web. The application and the database are both local to the IIS server and everything works fine except that the application and database are on four servers, so the database isn't centralized. To centralize the database, we experimented with a Network Appliance NetApp FAS270 with NAS configuration.

After comparing the performance of the NetApp configuration with the multiple-server setup, we realized that the NetApp solution returned results 20 times slower than the multiple-server configuration. Apparently the NetApp solution doesn't take advantage of the system cache, whereas the original configuration does. Do you have any suggestions for improving the NetApp solution performance?

I can think of a couple possible solutions for improving performance. I don't know how your systems are architected, so these solutions might not work for you, but one possible solution would be to access the FAS270 over iSCSI and use Network Appliance FlexClone to replicate the database volumes and make the database local to each server. The other solution would be to create a routine that downloads the database to your machines from the filer, possibly storing the information on a RAM drive to speed access. The downside to these solutions would be synchronization if each database contains disparate information.