Re: [PATCH v3 4/7] xfs: don't bump the i_version on an atime update in xfs_vn_update_time

[Amir Goldstein]

> > > >
> > > > Forensics and other applications that care about atime updates can and
> > > > should check atime and don't need i_version to know that it was changed.
> > > > The reliability of atime as an audit tool has dropped considerably since
> > > > the default in relatime.
>
> I've been waiting for Amir to appear in this discussion -- ISTR that a
> few years ago you were wanting the ability to scan a filesystem to look
> for files that have changed since a given point.  If XFS exported its
> di_changecount file attribute (as it currently behaves) via BULKSTAT,
> you'd have the ability to do that, so long as your application could
> persist bulkstat data and compare.
>

It's true that exporting i_version via BULKSTAT could be useful
to some backup/sync applications.

For my case, I was interested in something a bit different -
finding all the changes in a very large fs tree - or IOW finding if
anything has changed inside a large tree since a point in time.
So not sure if i_version would help for that use case.

Thanks,
Amir.