[Included text copied from the commit.] > Date: Sun, 24 Jan 2016 19:52:49 +0000 > From: samba-b...@samba.org
> Auto-Submitted: auto-generated > https://bugzilla.samba.org/show_bug.cgi?id=11521 > Wayne Davison <way...@samba.org> changed: > What |Removed |Added > ---------------------------------------------------------------------------- > Status|NEW |RESOLVED > Resolution|--- |FIXED > --- Comment #3 from Wayne Davison <way...@samba.org> --- > The latest git version has an option that lets you choose to include > nanoseconds in comparisons if you want them. Having it on by default would > likely cause far too many headaches for various backup solutions that use an > older filesystem (e.g. ext3) that doesn't support nanoseconds. Thanks for the patch! Just FYI, this comment is true but incomplete---the scenario I was describing was straight ext4-to-ext4 copies and/or backups. The timestamp problem I currently see with those is because rsync was throwing away the nanosecond information until this patch, even though both ends supported it. Anyone who's used dirvish, or presumably similar tools such as rsnapshot, from and to ext4 or other ns-supporting filesystems, will be bitten by the problem of non-ns vs ns timestamps bloating backups and breaking hardlinks, either when they manually use --modify-window=-1, or when this becomes the default. I'd still love to see either some in-rsync workaround that can be left in place*, or (second best) some clever by-hand one-time workaround that uses rsync just once to update all those timestamps while not breaking the hardlinks (presumably -not- using --link-dest for those), or (third best) some not-rsync-at-all solution that basically does a giant ls at the source and a giant touch at the destination. Yes, I know that none of those can fix up backed-up files that are no longer in the same place in the source; those at least won't bloat/ unhardlink later backups. This solution is likely going to have to be reinvented repeatedly by people running backups, so working out the right way to do it and then putting it somewhere other rsync users will find it is likely a useful exercise. Before I solve it by hand for myself, it'd be useful to know if it's likely rsync will come up with some way to solve it for me. * E.g., (a) "If modify-window is -1, and --link-dest is in use, and everything else about the file or directory matches -except- the timestamp, then update the timestamp," and (b) "Provide a switch to turn off this heuristic after I'm sure my backups are okay." (The intent of (b) is to catch later slight changes of timestamp but actually record them as -separate files-, which is important so older snapshots don't magically change out from under you if something updates a timestamp by a fraction of a second without otherwise changing anything, which does happen and can occasionally be -very- important to know about when tracking down issues.) -- Please use reply-all for most replies to avoid omitting the mailing list. To unsubscribe or change options: https://lists.samba.org/mailman/listinfo/rsync Before posting, read: http://www.catb.org/~esr/faqs/smart-questions.html