Photos for Mac Big Sur stuck on "Restoring from iCloud..."

Hi

What format and codec are the videos you uploaded. More than likely they are not compatible in some way with your mac, and that has stalled the synchronisation process. Unfortunately when this happens Photos/iCloud don't give any useful sort of error message.

A solution might be to remove those videos from iCloud, by logging on to:

www.icloud.com

with your apple ID.

See this article about what formats are no longer supported.

https://support.apple.com/en-gb/HT209029

Something has been broken with syncing from iCloud to Mac Photos in the last few months for me too. I also have a pretty big library, ~18,000 photos and ~800 videos. Photos and videos I take on my iPhone get uploaded to iCloud and sync to my iPad. They don't always make it to the Photos app on my Mac, which seems to get stuck all the time, though it's status claims "Updated Just Now". For example, it's currently about a week behind what I see in icloud.com and missing ~30 items. I have 7GB of free space and fiber internet so pretty sure those aren't issues.

I've had more than one support call with Apple and they walked me through creating a brand new photo library and re-syncing everything from iCloud. That worked in that it brought Photos on Mac up to date up until that point. But weeks later and a new version of MacOS (11.3.1) and Photos.app (Version 6.0 (340.0.221)) and the syncing continues to be broken.

Not sure when things broke but this all worked months ago without problems. These issues are making me reconsider whether I should be paying for and can trust iCloud with my data.

7GB of free space where?

If on your mac - this is barely enough to run the system, and may well be contributing to the problem of syncing new photos. You should consider either moving the library to an external volume (see link, particularly regarding the requirements for the external volume) or using "optimise mac storage" to move full size originals off your mac. (but then you have to worry about how you back up your library)

though it's status claims "Updated Just Now".

Updated just now means that Photos has updated all information about the library, but not, that all originals have been downloaded in the full resolution. If you are running low on storage, Photos will stop with downloading originals, even wit "Optimise Storage" disabled. Tony is right, that 7GB of "available storage" are needing attention immediately. I noticed on my Macs that even 20GB of available storage will make Photos pause with downloading originals.

whether I should be paying for and can trust iCloud with my data.

You certainly can trust iCloud with your documents and data, but iCloud does not suffice as a backup.

You always need an independent backup copy of your data, whether you are storing them in iCloud or locally on your Mac. Having your data only stored once and keeping working your only copy is a disaster waiting to happen. You need an independent copy of your documents and data and your photos that is kept safe and that you never touch.

Are you making regular backups with Time Machine? That would be the easiest way to keep your photos save, unless you are using "optimise Storage".

The problem did appear to be the lack of free space. With 30GB of free space, syncing is working again.

Well they are on the list. So it isn't that.

Wow - thanks for getting back and letting us know.

Well done - You've acheived the record for lenth of time of sync I have seen on these forums. 🙂