Either the kernel docs are wrong here or I am just a little drunk from christmas yet but I can see the difference when changing the overcommit_ratio. (Where did you find that it only works for overcommit_memory 2 ?) Also it makes no sense that it is set then by default if it isn't even used. So I suspect it is used. (also I can start a lot more apps with it set to 90 so it must have an effect)