System Data shows 97GB after deleting screen recordings on iMac

Give the Mac a day or so (24 hours) and you may see the storage space reduce itself to something more expected. At this point the space is likely available for use, but certain caches haven't been updated. It may take a little time.

Meanwhile...

What you can do…

• Empty the Trash in the Dock. 

• Empty the trash in the Photos app.

• Delete unused and unneeded application installers from your downloads folder and desktop.

• Reboot your Mac at least weekly.

• Transfer files that you don’t use daily to an external drive and then delete them from the startup drive and empty the trash. Files that take up the most room are movies, images and music.

• Force Time Machine to delete local snapshots:

About Time Machine local snapshots - Apple Support

• Use Disk Utility to delete APFS snapshots:

View APFS snapshots in Disk Utility on Mac - Apple Support 

This from Apple on the subject of storage management

Free up storage space on Mac - Apple Support

This is perfectly normal.

First off, when you 'delete' a file, it's not deleted immediately. This is especially true if you're using Time Machine backups of your device.

Time Machine makes file recovery easy since it maintains snapshots of the filesystem over time. Recent snapshots are kept on the machine itself (so you can instantly restore a file that you recently deleted), and older snapshots are moved off to offline storage if available.

So even though you have 'deleted' the files, they still exist in the snapshots, and get marked as System Data it's its part of a cache/backup, rather than normal user data.

The OS will automatically take care of cleaning that up over time. As the snapshots age, they'll get deleted, thus 'freeing' the space. The OS will also purge them automatically if space is needed for working documents (e.g. you download a new 10GB video file)

That's not out of line. Mine is:

System Data used to be called the Other Category in previous systems. The Other category is a potpourri of files which can include:

• System temporary files

• macOS system folders

• Archives and disk images (.zip, .iso, etc. - often found in the Downloads folder)

• Personal user data

• Files from the user’s library (Application Support, iCloud files, screensavers, etc.)

• Cache files: browser, Mail

• Mail messages & attachments

• Fonts, plugins, extensions

• Safari reading list

• iTunes backups

• Crud resulting from jailbreaking your iDevice

• Game data

• Saved data files

• Call history

• Notes

• Media

• Voice memos

• Other files that are not recognized by a Spotlight search

• Media files that cannot be classified by Spotlight as a media file because they are located inside of a package

• Files created and modified by other user accounts on your Mac.

They can be located anywhere on your hard drive.

The files that you have control over are located in the Documents, Downloads, Pictures, Music and Movies folders.  You can use either of these two free apps, GrandPerspective  or OmniDiscSweeper, to find the largest files on your drive so you can determine if they can be deleted or moved to an external HD for storage.  

Note: you can empty the Downloads folder after the apps and/or updates that were downloaded have been installed or applied.  Many users have found a couple of Gigabytes of files in their Downloads folder which are no longer needed. 

Mornathor wrote:

thanks, [...] but I still got like 1.5gb free on my whole iMac (I just deleted around 100gb worth of screenrecordings)

seems like it need some time to catch up with recent deletes

You're welcome.

Please know that 1.5GB free space is critically low, though I understand that doesn't account for what you've just deleted. You should seriously consider using an external drive to store the majority of your user files. You can direct most, if not all, of your apps to store their data to the external drive, including your screen recordings. This will let you breath easier when using your Mac and not have to micromanage the storage. If the free space is allowed to drop too low, you run the risk of the Mac being unable to startup at all.

You might also consider using Optimized storage to keep a little extra space available on the computer when you need it. Files can be kept on your iCloud drive and off the Mac, while still being instantly available.

Optimize storage space on your Mac - Apple Support

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