[Koha] Slow system

We have a library that has created a patron for a room were they store books that aren't being used. There are hundreds of books checked out to this patron. What they are noticing is that the system slows down significantly when they are checking out to this patron. Does anyone have a solution to this problem? We are running Koha 3.2 Thanks, Marie Wardall Library Media Specialist Mountain Bay Elementary School Weston, WI 54476