Does Multi-core JIT works on WPF(.NET 4.5)?

My PC's configurations: Windows 7 Pro 64 Bits, CPU is XEON E3 1225 and 8GB Ram

After I run the following codes in public App(), the Profile Root folder doesn't appear and the Profile File either.

ProfileOptimization.SetProfileRoot(AppDomain.CurrentDomain.BaseDirectory + "StartupFolder");
ProfileOptimization.StartProfile("ProfileFile");

Am I missing something? or it doesn't work in WPF? Thanks.