Overcommit ratio settings for Android? (Kernal Adiutor)
My understanding is this. basically the android system runs all the apps and determines when to give them memory and how much. when an app requests some RAM the system will set aside some ram for that app.  apps dont always use as much ram as they request, so the system will actually tell the app it has X amount of RAM to use when in reality only Y amount of ram was set aside and X>Y is the ratio essentially. 
so 50% would mean that the system would attempt to set aside 50% less physical memory to this app than it wants but keeps it a secret from the app and then uses multitasking in order to try and give it ram as needed