Most of the time, you want to use RAM as a cache for the disk. I was trying to make the argument that sometimes that disk cache is more valuable than an under-

Most of the time, you want to use RAM as a cache for the disk. I was trying to make the argument that sometimes that disk cache is more valuable than an under-used anonymous mapping. Steve has responded to your comment about Rust; to your other comments: Modern applications do a lot more than old ones. Even if you only use 20% of the features, you probably use a different 20% from any arbitrary other person. You also probably benefit from the OS being able to map everything into virtual memory but only actually load the bits you use :). And I strongly disagree with your stance on being "serious". I'm sure you don't mean to gate-keep, but we need to teach people where they are rather than giving them hoops to jump through. In my experience, some of the best software engineers have very little development background. And I say that as someone who implemented 64-bit integer support for the compiler and RTL for a DSP part back in the day. It's useful to have people around with a variety of backgrounds, it's not necessary for everyone to share any particular experience.