MacOS Free Drive Space Shrinking!

Happy new year!

I have an issue with my MacMini (2012) server which is running latest Catalina on a 1.12TB fusion drive set as APFS.

I only upgraded from Mojave in the last couple of weeks and so I am unsure whether that has been the trigger…

My disk free space is getting smaller and smaller and is now just 136GB; I estimate I only have 200GB of actual files on the drive. When inspecting Storage under About this Mac the ‘Other’ category is using 753GB.

I need to recover this space.

I think it could be something to do with either

a) time machine (I’ve turned it off but this hasn’t helped) or

b) photo library. This was previously all originals but I changed to optimised and is now taking up 50GB (full originals is about 550GB). Could the OS not have recovered this space once I switched to optimised?

Any help much appreciated. Thank you.

first of all: happy 2020!

In this case it’s probably APFS snapshots for time machine? That tends to fill up my SSD as well. APFS treats all your free disk space as a resource, and fills it with backups

But, why would you have the need to reclaim the space?
I’ve found that since Catalina (even Mojave) I let macOS manage free space, and it usually works out fine, I’ve never run out. It looks weird, having a drive with wildly swinging free-empty numbers, but the system seems to know what it’s doing.

Thanks for the reply. I’ve turned off time machine today and removed the old time machine drive from settings (that wasn’t attached anyhow) and rebooted and will see if that helps. I’m assuming if I’m not running time machine then the snapshots will disappear over time?

It’s just a little unsettling that It’s showing c. 10% of the drive is free and nearly 75% is taken up by ‘Other’.

From Apple Support: :bellhop_bell:

If you want to delete local snapshots manually, turn off Time Machine temporarily:

  1. Open Time Machine preferences from the Time Machine menu in the menu bar. Or choose Apple menu  > System Preferences, then click Time Machine.
  2. Deselect ”Back Up Automatically” or click the Off/On switch, depending on what you see in Time Machine preferences.
  3. Wait a few minutes to allow the local snapshots to be deleted. Then turn on Time Machine again. It remembers your backup disks.

I think we’re conditioned to look at the disk capacity constantly and try to manage it, because that was very important.

Over the past year I’ve let that go (a bit) and found that my Apple devices are quite capable to manage space themselves, and that the built in mechanisms work very well.