EWF-Ram overlay fillup when running RDP session

Hi,

I am testing my new build, running EWF-Ram with a RAM-Disk that gets all IE
cache and Temp data.
while running a terminal-services RDP session for a few minutes, I saw the
EWF overlay gets filled.
from a starting point of:
Memory used for data 3354624 bytes
Memory used for mapping 4096 bytes
it quickly got to:
Memory used for data 22933504 bytes
Memory used for mapping 20480 bytes

I will also use ICA sessions and I know how to change the bitmap cache and
logs through the AppSrv.ini and WFClient.ini files.

what am I missing here?

thanks,

YaronM