Comment by vacuity

What are examples of the MMU leading to poor abstractions? I agree it's not ideal, and encourages some poor abstractions, but I think it's moreso the case that mainstream operating systems have failed to innovate sufficiently. For example, the notion of a 1:1 bijection of address space and process doesn't have to be the case, but it is, I suppose, the most obvious use. (There is vfork(...), heh.)