After MAC OS 12 Monterey update that System Data Folder swelled to incredible 320 GB

GREAT FIX THERE APPLE, CHANGED ALL OF THE WASTED SPACE FROM "OTHER" TO "SYSTEM DATA" STILL TAKE UP 625GB OF A 1TB

MAIN HARD DRIVE???

Hi

. . . I am able to recover 40 GB of system data . . .

(I apologize for my poor english)

I was having the same problem with my big pig. I was very worried .. I thought maybe updating Monterey would solve this problem ... After the update I saw 20+ vacancies I was happy at first but soon I realized That place was actually the OS installer. Files that were removed after installation.

Following these steps, I am able to recover 40 GB of system data.

This space was previously 124+ I didn't take any screenshot before.

I first run the following command in the terminal and it creates a 20GBs file in the user's folder. (I don't remember where I got this command from .. I guess some stack overflow)

dd if = / dev / urandom of = temp_20GB_file bs = 1024 count = $ [1024 * 1024 * 20]

I deleted this file.

I once again created several small files to see how much space could be occupied.

dd if = / dev / urandom of = temp_5GB_file_1 bs = 1024 count = $ [1024 * 1024 * 5]
dd if = / dev / urandom of = temp_5GB_file_2 bs = 1024 count = $ [1024 * 1024 * 5]
dd if = / dev / urandom of = temp_5GB_file_3 bs = 1024 count = $ [1024 * 1024 * 5]
dd if = / dev / urandom of = temp_5GB_file_4 bs = 1024 count = $ [1024 * 1024 * 5]

All the files here are with different names (temp_5GB_files_X, this is X not much writing change)

Then I thought of making a big file of 20 GB.

dd if = / dev / urandom of = temp_20GB_file_1 bs = 1024 count = $ [1024 * 1024 * 20]

But I could not create a file of such a large size but I could create a file as large as the space was available.

At this level .. I only had 233MBs of space left. And the System Data was still using 124+GBs.

I rebooted my MacBook in Safe Mode, pressed Shift on Reboot and put it in Safe Mode .. I noticed .. System data was reduced from 124 + GBs to 87GBs.

Here I run the same command to create temp files on the terminal to capture this space.

dd if = / dev / urandom of = temp_20GB_file_safe_1 bs = 1024 count = $ [1024 * 1024 * 20]
dd if = / dev / urandom of = temp_20GB_file_safe_2 bs = 1024 count = $ [1024 * 1024 * 20]

This picture is a sample .. I didn't screenshot any image before.

And it can help me capture as much space as possible.

Remember that the larger the space, the larger the file.

I rebooted into normal mode.

I was happy that now the system data is using only 86GB of data .. it has not been expanded.

See above - System Data is using only 86+GB. all above listed information is exact as expected.

Now I checked in the system storage .. which files are using space ..

And this made unhide hidden files.

I opened finder and hit

Command + Shift + .  (dot)

Other than Library folder.. all files in my user are 56+GB (excluding my temp_files)

and this Library folder is taking. all of the (hidden system data kind of information.)

Inside this Library.. Developer (XCode) taking 65GB.. Andrdoid SDK (17GB) and Mobile sync in Application support folder is taking 28GB.. so.. Library is showing absolutely correct data.

... further more.. in diskutil list

In a rough calculation.. out of 500GBs ssd..

100GB is for bootcamp
400GB is for my macOS
-out of 400GBs..
My second drive is 100GB est
-Out of 300GB
OS is 15.8GB
OS update and snapshot 15.8GB
My user folder = 265GB
some preboot and Recovery firmware = 2GBs
=== So 265+16+16+2 = 300GB (est)


So far now.. everything is pretty clear. I hope this might help to understand.. where all of the space is going.

if you don't need XCode.. remove that folder.

if you are taking many backups os IOS Devices.. Remove them and keep the latest one.

No that is not replicating.. that is just a shortcut (alias) of the same parent drive. so.. opening it will open it's parent again and again. If you check file size in file info.. ( command + i ) .. it will be around a few bytes.

Disconnect all External Drives then run this command from Terminal and post back a Text of the output.

 diskutil list

I decided to start again, doing a clean install instead of using Migration Assistant. And lo and behold, all the 500MB of 'system data' has gone from the hard drive.

Q