Re: noatime mounts inhibiting atime updates via utime()

[Greg Troxel <gdt%lexort.com@localhost>]

Edgar Fuß <ef%math.uni-bonn.de@localhost> writes:

>> Honestly, I think atime is one of the dumbest thing ever.
> We occasionally use them to find out (or have a first guess at):
> -- has anyone used libfoobar last year?
> -- who uses kbaz, i.e. has /home/xyz/.config/kbaz.conf been accessed?
>
> We use snapshots to run backups, so atimes are not touched by them.

I fairly often look at atimes to find out if old libraries have been
used, and various other things.

I have also had a test that tried to use utime fail on a machine that
was noatime.

So the notion that noatime should mean what it does now, but allow
explicit writes sounds good.

I don't see any value in changing the naming of the flags.  Having a fs
write atime updates unless mounted noatime seems fine, and if people
want noatime that's easy.  I would be opposed to e.g. dropping the
noatime option, making noatime default, and adding an atime option.
That's just churn violating historical norms for no good reason.

There's a question of what the default for installs should be, and I
don't have a real opinion about that.


It would be good to have stats about writes, separately including atime
updates.  Right now we know it causes writes but I haven't seen data.