This may be of interest for all developers.
I just received the following answer from the SAP Customer Support regarding the large footprint of an Add-on using the DI.
"Just got reply from developer side.
It is a normal system behavior and not a problem.
Currently, a DI connection will use about 50 MB and UI connection will use about 10 MB memory.
For the case I mentioned the memory will be decreased when you minimize window, in fact, it is because windows use Virtual Memory instead of Actual Memory, it is still not changed.
I am sorry about any inconvenience, we will try to improve system performance in the future version."
Well, I think the memory load is a problem, especially when several Add-ons using the DI are running...