Disk Usage by "System"

[sgharp]

Hi,

I have a mid-2012 MacBook Pro with a 750GB SSD. I've been fighting with frequently running low on disk space for some time. I noticed today that "System Information/Storage" shows that "System" is using 532GB or more that 70% of my drive. My entire user directory uses less that 200GB and I'm still running out of space. How can so much space be allocated to System and how do I free it up?

Thanks for any suggestions....

 

[Wildkraut]

Do you have trim enabled for the SSD?

 

[sgharp]

Do you have trim enabled for the SSD?

I don't. After reading up on it, I'm not sure I want to. Apple doesn't really ensure results.

Why do you think this would fix the problem?

 

[xraydoc]

There's a number of apps that will show you what is using all your space. One I like is Daisy Disk. It's a few bucks on the Mac App Store.

 

[sgharp]

There's a number of apps that will show you what is using all your space. One I like is Daisy Disk. It's a few bucks on the Mac App Store.

I've used OmniDiskSweeper and it only shows a little over 200GB used. However, OSX System Information shows almost the whole 750GB used. When I use a terminal, df also shows the drive almost full.

 

[HDFan]

I would check that OmniDiskSweeper is giving the correct results. On my system it hung on the Users directory, the most likely place you could be using a lot of space.

It was also quite slow. I could have done multiple DaisyDisk full volume scans scans while Omni was just scanning one large directory (Users). If you don't want to use DaisyDisk you might try to find another scanner to make sure that it gives the same results.

Here are the screenshots of my results. I gave up waiting for Omni to finish after ~10 minutes so it is still chugging along. After ~30 minutes I updated this post with the "maybe a bug" comment. [This drive is an SSD on a 2013 nMP].

 

[maflynn]

I would check that OmniDiskSweeper is giving the correct results. On my system it hung on the Users directory, the most likely place you could be using a lot of space.

Omnidiskspace dose not have the rights to access some system files and so it will under report them

If you run it with sudo (As shown below), it will include some system files that it woud not normally have access to scan. That is a more accurate representation of what's consuming your drive.

sudo /Applications/OmniDiskSweeper.app/Contents/MacOS/OmniDiskSweeper

Another option is to use this terminal command
sudo du -d 1 -x -c -g /

I prefer to redirect it to a text file (this puts it in your Documents folder
sudo du -d 1 -x -c -g / > ~/Documents/du.txt

Like the sudo /Applications/OmniDiskSweeper.app/Contents/MacOS/OmniDiskSweeper command, it will scan all directories, but produce a text file as opposed to showing the results in a window

 

[Wildkraut]

I don't. After reading up on it, I'm not sure I want to. Apple doesn't really ensure results.

Why do you think this would fix the problem?

Because it looks like macOS isn't communicating right with the SSD.
I think it's full because there is a lot of sector garbage left on then SSD, means they not flagged as free space for/by macOS.
Trim is exactly to avoid this.

https://en.wikipedia.org/wiki/Trim_(computing)

 

[sgharp]

Omnidiskspace dose not have the rights to access some system files and so it will under report them

If you run it with sudo (As shown below), it will include some system files that it woud not normally have access to scan. That is a more accurate representation of what's consuming your drive.

sudo /Applications/OmniDiskSweeper.app/Contents/MacOS/OmniDiskSweeper

Another option is to use this terminal command
sudo du -d 1 -x -c -g /

I prefer to redirect it to a text file (this puts it in your Documents folder
sudo du -d 1 -x -c -g / > ~/Documents/du.txt

Like the sudo /Applications/OmniDiskSweeper.app/Contents/MacOS/OmniDiskSweeper command, it will scan all directories, but produce a text file as opposed to showing the results in a window

This was the solution. Running OmniDiskSweeper as a regular user prevents it from accurately reporting. I ran it as root and it turns out that /var/root/.cache was using over 400GB. Looks like leftovers from failed duplicity backups.

Thanks very much! You save my bacon.

 

[Oleg K.]

This was the solution. Running OmniDiskSweeper as a regular user prevents it from accurately reporting. I ran it as root and it turns out that /var/root/.cache was using over 400GB. Looks like leftovers from failed duplicity backups.

Thanks very much! You save my bacon.

Just FYI, there is "Scan as Administrator" command in DaisyDisk, which is essentially the same as running the app with sudo, but in a more convenient way. See https://daisydiskapp.com/manual/4/en/Topics/AdminScan.html