Hello,
I have using FFS for mirroring my apple photo library for a few years.
FFS allows me to backup my entire photo booth also to review which files has been modified/deleted
so that it is worry-free for the icloud's silent corruption.
It works so far before I switched to a new macbook.
The whole photo library has to be download again from icloud to the new macbook, as such the file creation time are different (a huge one, more than a decade).
I have checked manually the file structure, name, and content (by md5) are the same.
I also compared the file with "content" in FFS, but it failed.
Only 39 files (actually some of them has a 5 years diff in creation time) among the 50000 are the same in FFS result.
The comparison took only 2-3 seconds which make me think that FFS has skipped the real content checking.
Am I using FFS incorrectly? or it is a bug? or is it intended?
Thank you.
Failed comparison of same filename, structure, huge different in create time
- Posts: 3
- Joined: 29 Jul 2026
- Posts: 1239
- Joined: 8 May 2006
These 49961 files, are they, the left/right pairs of each file, of different sizes?
If so, they cannot be content identical, so no need to actually compare any content, hence the check can be very quick.
If the pairs of files are of different sizes, possible that some meta-data was added to the file?
At that point, a comparison of said files might point out what is going on.
(WinMerge, or similar might do the job.)
If the pairs are the same sizes, then something else is going on.
(If FFS stores the .db, does that include hash... no, it would not.)
If so, they cannot be content identical, so no need to actually compare any content, hence the check can be very quick.
If the pairs of files are of different sizes, possible that some meta-data was added to the file?
At that point, a comparison of said files might point out what is going on.
(WinMerge, or similar might do the job.)
If the pairs are the same sizes, then something else is going on.
(If FFS stores the .db, does that include hash... no, it would not.)
- Posts: 3
- Joined: 29 Jul 2026
They are in the same size and same name. I have also checked their md5 hash value for some pairs, which they are the same.
so I am gucessing there are something else, either some missing metadata or FFS behaviour.
so I am gucessing there are something else, either some missing metadata or FFS behaviour.
- Posts: 3
- Joined: 29 Jul 2026
It turns out that should be a weird behaviour of Mac. The files I used for md5 check manually on the above is some how being removed on Mac photo library when I am doing the check for another file. It keeps downloading and removing but the app said the download is completed (file count and total size in quick review), and so the equal files number keeps steady at 39. I recreated the library and force it download the original files completely with Airdrop. It works now.
That's why I am doing mirroring with FFS. Some of my old videos lost their audio track but I don't know y.
Thank you for your attention and support. Thank you FFS for saving my video.
That's why I am doing mirroring with FFS. Some of my old videos lost their audio track but I don't know y.
Thank you for your attention and support. Thank you FFS for saving my video.
