Apple Photos Library on an APFS Volume

Does anyone have experience with running Apple Photos on an APFS Volume with a size quota to keep it from filling the whole SSD? I know this works in theory, but I’m curious if this works well or not.

Here’s the full situation:
We have a ~400GB Apple Photos library that is synced to iCloud Photos with my wife’s Apple ID. I have a Mac Mini with a 1TB data drive that keeps the full Apple Photos library in sync, which is then backed up with Time Machine, SuperDuper drive clones, and Backblaze. I also run Google Backup & Sync to sync the photos up to Google Drive Photos for an extra safeguard and so that I can view the family photos on my phone.

This all seems to work fine, except that I’d like for my wife to be able to run Apple Photos on her MacBook as well (the Mac Mini will still be the “home” for the photos and run the backups—her MacBook would just be for viewing/editing). In the past, we tried this with the Optimized Storage setting in Apple Photos turned on. But, this invariably still filled her hard drive, causing us to have to remove the Apple Photos library from that machine.

I have heard on some podcasts as well as in a few blog posts that you can create a new APFS Volume and set a quota on it. Putting the Apple Photos library on that and choosing optimize storage would thereby restrict how much space Apple Photos can hog on the system.

My question for you here is have you done this and have you encountered any issues that I should be aware of?

Marco Arment described exactly this approach on Accidental Tech Podcast a while back. He uses it and I used it for a while, too, but ended up with a different computer without the restricted space and didn’t continue it there. You could try asking him on Twitter if he’s still using it. @marcoarment

1 Like

I should have said ATP is where I got the idea. Thanks for sharing your experience!

The data drive on my Mac Mini seems to be failing and it is old so I have just ordered a new Mac Mini M1. Everything is backed up but I don’t want to try something new while the main machine is limping. When that comes in and I can confirm things are running smoothly again, I’m going to try this method.

1 Like


I never hit the limit I set so I don’t know how it behaves at that point, but logic says it should work as the volume should be a hard size limit at the deep OS level and so Photos will just believe it’s on a small volume and purge.

@thatChrisHarper Did you end up doing this plan for photos? How has it worked?