Why is macOS 15 consuming so much disk space?

AOrlandini wrote:

• Sure, emptying the trash very often... sigh.

You don't need any 3rd party security apps on a Mac.

However, that has nothing to do with your storage problems.

The first thing to know is that this actually doesn't have anything to do with "System Data". I know it says that. It's totally lying to you.

It is better to think of this as "Other" data. I can't tell you what that other data might be. It's a recursive definition. "other" data is any data that can't otherwise be categorized. The only way I can make this more confusing is to call "other" data something that it isn't, like "system" data.

The operating system tries to categorize all of your data. So it groups things into "Moves", "Pictures", "Documents", "Apps", etc. But for anything that doesn't fall into one of those recognizable groups, it calls "System Data". And it's wrong.

What you have to do is use one of those storage management tools to find where this storage is being used. Since you've already installed EtreCheckPro, you have one, built right into EtreCheckPro. Go to the Tools menu and choose "Storage...". You will have to give EtreCheckPro Full Disk Access for this. That would be true of any such storage tool.

The EtreCheckPro Storage tool will show you a pie graph of how your storage is physically allocated on disk. You can click on each pie piece and drill down into the folders that are consuming the indicated amount of storage. You should eventually find some folder that has way too much storage being used.

Just be careful. You should really only delete files that you created. If you try to delete any other files, there is a risk of unrecoverable data loss. Be particularly wary of any "Library" folder. This is where apps like to store random stuff. Sometimes they go wild and write some log file out of control, or something. You can delete those files, but you might break some app that needs them. And that might have been an app you had important data in. And maybe the app syncs your file deletion with the cloud and deletes your data on all your devices.

This is why the EtreCheckPro Storage tools greys out these "Library" folders and disables the "Show in Finder" button. You can still drill down into them and see how the storage is allocated. But be careful!

Here is an example from the other day when someone used the EtreCheckPro Storage tool to find the cause of their storage problem: Full Storage on MacBook Pro - Apple Community

This is also a cautionary tale. I wasn't sure how to handle the storage in this case. I don't know if that problem ever got resolved. Such is life in the forums.

From the Etrecheck Report >> Avast <<

Avast AntiVirus

FTC Order Will Ban Avast from Selling Browsing Data for Advertising Purposes, Require It to Pay $16.5 Million Over Charges the Firm Sold Browsing Data After Claiming Its Products Would Block Online Tracking 

FTC says despite its promises to protect consumers from online tracking, Avast sold consumers' browsing data to third parties

https://www.ftc.gov/news-events/news/press-releases/2024/02/ftc-order-will-ban-avast-selling-browsing-data-advertising-purposes-require-it-pay-165-million-over

Once this type of software is installed and embedded into the computer >> Avast Antivirus software

You can spend hours or days hunting down all the bits and pieces of this software and never really get it all off the computer 

Start Over from Scratch 

For Apple Silicon computer >> Use Disk Utility to erase a Mac with Apple silicon.

For Apple Intel computers >>   Use Disk Utility to erase an Intel-based Mac followed by How to reinstall macOS

Always make a Time Machine Backup  before  proceeding 

If going this route - I suggest Not using Startup Assist to migrate everything back.

This will probably Re-Introduce ( Avast Antivirus software ) back into the Operating System 

From the After Avast Removal report

" Time Machine backup out-of-date - The last Time Machine backup is over 10 days old. "

How to delete Time Machine snapshots on your Mac.  

Often caused if the Time Machine Drive has not been attached  to the computer and TM Backup is set to run on a Schedule. 

TM Backup will make Snap Shots on the Internal Drive awaiting the TM Backup Drive to be attached. 

Only then,  will the Snaps Shots be transferred to the External Drive.

In Disk Utility>View, select Show all Devices, highlight the top left entry.

Run Disk First Aid on all items in the left panel, from top down.

Are you running any VPN, Anti-Virus, or Cleaning apps?

We need to see what all is running, a report from this will not display any personal info...

Using EtreCheck - Apple Community

EtreCheck is a FREE simple little diagnostic tool to display the important details of your system configuration and allow you to copy that information to the Clipboard. It is meant to be used with Apple Support Communities to help people help you with your Mac. It will not display any personal info. Give it Full Disk Access.

https://www.etrecheck.com/

Give etrecheck Full Disk Access before running.

Thanks for Old Toad’s etrecheck instructions…

Slow iMac 2017 - Apple Community

Uninstall Avast (is VirusBarrier related to it?). 3rd party virus apps produce obscure errors and are not needed. macOS handles that task by itself.

I'd uninstall OpenVPN unless really needed.

Check and maybe delete extra snapshots via Disk Utility or Carbon Copy Cloner although extra snapshots should usually deleted automatically.

You do have 162 GB in Mail too. For comparison, I've tried to save every e-mail since the 1990s and I only have 11 GB. That Spotlight data might be directly proportional to your Mail usage. If so, there will be no way to fix this problem.

You might consider cleaning out some of that mail.

Just checking, you are emptying the trash?

Unistall Avast per their directions , then run etrecheck again to see what chaff it left...

On AVG & Avast…

I get a access denied error when trying t… - Apple Community

https://x704.net/bbs/viewtopic.php?f=17&t=8803&p=115715&hilit=avg#p115715

https://discussions.apple.com/thread/251454104?answerId=252862395022#252862395022

https://www.ftc.gov/news-events/news/press-releases/2024/02/ftc-order-will-ban-avast-selling-browsing-data-advertising-purposes-require-it-pay-165-million-over

I like the way you have represented the output of the Storage tool.

But are you sure that's correct? I'm seeing those items under "/Users/myuser/Library/Metadata/CoreSpotlight"

I think you can safely delete the "CoreSpotlight" and "com.apple.IntelligentSuggestions" folders. Then restart.

I also recommend restarting your Mac in Safe Mode, as described here: Start up your Mac in safe mode - Apple Support

In theory, this is supposed to reset certain system caches. Maybe these new Spotlight AI files will be included.

As much as I I respect the contributions r of all others.

There are two distinct issues at play

Yes, lack of Empty Space and Yes the Third Party Security Software used and installed on the computer

You can address the empty Space Issue via the various method already suggested

The computer may function and limp along

The caveat being, Third Security Software, that even once removed, it may already compromised the operating system in ways you will only find out at sometime in the future

the same to you , I found the folder ： SpotlightKnowledgeEvents/index.V2/events/10/keyphrases/cs_pc_c

become larger and larger