Environmental considerations

Resource management is different - If your cross memory programs invoke programs in other address spaces, you might need to manage resources differently. For example, your cross memory programs must be able to handle the situation that occurs when an invoked program in another address space abnormally terminates.
Accounting methods might be affected - Your cross memory programs might acquire the ownership of resources on behalf of cross memory users. You might want to account for these resources differently than the way you account for your own resources.
The execution time of PC routines is attributed to the home address space, which may not be the address space in which the program executes.