> Converting most reads into a read and a write is such an obviously horrible idea that one should not even have to argue about it
The "converting reads into write" argument is very nice (and lyric), but it's not particularly compelling. atime is not changing the intrinsic nature of reads. atime is a logging/accounting mechanism like many others that an OS kernel implements. It is in the nature of accounting to consume space and that happens (inevitably) also when you log actions that, per se, wouldn't have consumed any space. I don't see any inherent flaw in that, it is "just" a matter of difficult trade-offs about where to store the information and how to minimize their size when space is tight.