In your example QlikView is using 85% of RAM with a QVS_Min set to 90% right?
This would allow for 5% or roughly 50GB of Data to be available until QlikView starts purging cache to make room for new material. This does make sense as you are talking about 20 apps. 1024 GB / 20 is just those 5%.
QlikView internal engine has a highly sophisticated method for determining what to hold on memory. Items are evaluated on how costly they are to calculate, their age, their commonality and several other parameters.
I suspect that in this case you are seeing QlikView determining that removing one app that hasn't been used recently is the best way to deal with shortage of RAM.
To the best of my knowledge there is no setting for max amount of apps that can be used at any given point.
Hampus von Post,