MacOS Sequoia filling up with system data

Exact same story here with Mac M1 Pro - Sequoia update exploded the system data and deleting items from documents seems to only shift data from there to system. I trashed 260GB of video from documents and saw a corresponding increase in system data. I don't use time machine. Other fixes suggested don't do anything. Lack of free space seems to be causing other buggy issues with performance and random rebooting. Would love an actual update to fix this, or easier way to downgrade to macOS 14.

I'm also drowning in (428GB of) System Data. It seems it doesn't even matter if I'm removing other files from my laptop, I'm not getting any space back.

What seems even weirder is that I can't seem to find where these 400GB are hiding...

So, if I understand correctly, each week or so I need to go into safe mode, delete the system caches to free up 560GB of system data? I am not sure this is a good long term solution.

This has become a huge problem for me. I have 3 Mac's and all of them have had this issue since updating to Sequoia. I have a new Mac Pro that is 3 months old with a 1TB harddrive and the System Data has been growing every day. It got to 600GB and I loaded an older version of the machine in and watched the system data. It just seems to grow unchecked until I run first aid. This reduces the system data down to less than 1GB of space. Over time it grows. Right now it is 383GB and it has been 5 days or so since I ran first aid on the hard drive. HELP from someone from Apple would be helpful.

I have the same issue since upgrading to Sequoia: lots of space before, full disk after.

As @DGaryC said, this has nothing to do with normal files in Documents, Downloads, Photos, etc. It's a sudden bloating of System Data after upgrading to Sequoia.

Hi,

Your Mac “System data” contains files that don’t fall into the categories listed here (Apps, Document folders, iCloud Drive, iOS Files, TV, Music, Books, and Podcasts Mail, Messages, Music creation, photos, trash, apps and files from macOS). 

This category primarily includes files and data used by the system, such as log files, caches, VM files, and other runtime system resources. Also included are temporary files, fonts, app support files, and plug-ins. You can't manage the contents of this category. The contents are managed by macOS, and the category varies in size depending on the current state of your Mac.

You will have to navigate through your files in library to clear this " system data". I have created a video about this with steps.

You can have a look and see if you are able to follow it : https://youtu.be/9P4oqri4dYc?si=1WT4JKtmYfdnfTrd

Spotlight or more precisely mds_stores is writing huge amounts but they are disappearing instantly and NOT filling up my drive.

However it is still creating immense wear which will eventually destroy my SSD.

The only "cure" I have found is to drag all my drives into the "do not search" box of Spotlight in System Settings.

This has reduced the total writes from over 100 GB per day to a normal 12 GB daily but of course it means Spotlight won't work.

I've never found it to be much good so I am not too bothered by its loss but it would be nice to have a fully functional machine even though I don't need it.

Not yet but I have an open support case with Apple on this. I have spent countless hours on this and up to this point, over three hours on the phone with them trying to figure out what is going on. I have run several rounds of diagnostics and provided the output to them which hopefully will reveal root cause.

My scenario is my 1TB drive has 680GB being eaten up by system files.

Will share what I find out

I have read through all of these posts related to this issue and while some of the troubleshooting steps such as cache clearing, booting to safe mode, culling TimeMachine entries, downgrading to a previous OS, etc., none appear to address and remedy root cause.

I have a case open with Apple and hope to be able to get to the bottom of this and remedy the issue without having to wipe my drive and start over. That is a solution that none of us should even remotely consider as acceptable!!

There has to be a fix to this problem and if any of you reading this are experiencing a similar issue, please contact Apple and open a support ticket. The more official visibility this has the more likely we are to get a resolve!

I'm not as technologically sophisticated as anyone in this thread. But to my simple mind, it seems counter-intuitive that I should have to delete photos, videos and other documents I keep on my hard drive just to allow the system data to take up 75% of the total volume. I mean: isn't that the purpose of my hard drive, to store stuff I want?

I'm not sure when the system data started to balloon like this, but my machine is really struggling under its weight (1.5 TB out of 2 TB total storage).

(Mac Mini 2018, Quad-Core Intel Core i3; Sequoia 15.3)

Since macOS Sequoia, there is a way to link files and folders similar to a hard link that is only available for macOS. This is called a "firm link". Such "firm links" cannot be created by the user. These "firm links" are used to link the user-writable folders on the boot disk to /System/Volumes/Data. Apparently, the built-in terminal tools such as 'du' or 'df' as well as the third-party desktop app 'DaisyDisk' cannot yet handle these new "firm links" correctly in every case and the disk space for the linked areas may be counted twice. This mainly affects the content of /Users, /Applications and /opt

I'm having the same issue. Most of my data is stored on hard drives so my macbookpro doesn't really store much but applications. Since upgrading to Sequoia the system data takes up 250GB which makes me wonder if this is a way for apple to force users to purchase iCloud space. Can't seem to wonder why it's taking up so much space.