Since updating to DNN 8 I've had a strange problem with some custom modules we've developed. A few of our custom modules allow viewing profile information for several users on a site (in some cases 50-100 users). Since the update pages using UserInfo.FirstName, UserInfo.LastName, or any other properties that call to the UserProfile object run extremely slowly - enough to crash the page if there are several such calls. Any idea why this might be happening or what could be done about it?

As an example, here's one piece of code that causes problems:

foreach (Reservation r in reservations)
{
    UserInfo user = UserController.GetUserById(PortalId, sr.StudentID);
    r.Name = user.LastName + ", " + user.FirstName;
}

Thanks in Advance.

My understanding is that UserInfo objects are stored in memory via the caching provider. Is that no longer the case? Also, it seems strange that the UserInfo.FirstName and UserInfo.LastName call out to the Profile object while DisplayName just grabs directly from the Users table, especially since FirstName and LastName are columns in the Users table as well.