it's default off of course. A distro can turn it on or off.
i've periodically pushed for a noatime distro kernel for like ... 5-10
years and last time this argument came up [i brought it up 6 months ago]
most of the distro kernel developer actually recommended using noatime,
but it took only 1-2 kernel developers to come out with the
'compatibility' and 'compliance' boogeyman to scare the distro userspace
people away from changing /etc/fstab.
so yes, things like this needs a clear message from the kernel folks,
and a kernel option for that is a pretty good way of doing it.
Ingo
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