In netmrg, the mathematical capabilities on monitors are only "multiplier by a fixed value".
It is enought for a single monitor but the possibility to do mathematical operation beetween two monitors will be a plus.
For exemple with windows you could get two different monitors for "commit limit" and "commited bytes". But neither are really useful. What is needed is "available commit" which is "commit limit" - "commited bytes".
I think about a virtual monitor whose values come from other monitor with a CDEF expression.
Can this possibility be considered?
This is something we are planning to do, but it isn't on the top of the list at the moment. Bug#205
is pretty much this issue, although the description in the bug leaves something to be desired.