MacOS Sierra - 50-100GB of system storage??

First to gave a few GB space so you can download an app to find large files....

In System Preferences

* Time Machine, turn off Time Machine. This will delete any local Time Machine backups.

* Drag your Macintosh HD to the privacy tab to stop Spotlight and delete all Spotlight cache files.

Empty the Trash

Delete items in Downloads

Open iPhoto > Control (right) clicking on iPhoto’s Trash icon and choosing Empty Trash from the contextual menu.

Open iTunes > Preferences > Devices .... delete all old backups

Free up storage space on your Mac - Apple Support

How to Find Items Based on File Size on a Mac (This works to locate large files and items in all versions of OS X:)

• From the Mac OS X Desktop, open any new Finder window
• Hit Command+F to bring up Search
• Click on “Kind” filter and select “Other”, then select “File Size” from the attribute list
• Click on the second filter and choose “is greater than”
• In the third space, enter the size to search for anything greater than (ex: 100) and choose either MB or GB as the final filter

Now that you have some free space, download OmniDiskSweeper (free)

http://www.omnigroup.com/products/omnidisksweeper/

**Show User's Library

The User's Library folder is hidden by default. To unhide: Select the Finder in the Dock. Under Go in the Menu bar > hold down the Option key and you’ll see the Library.

I faced the same problem just today and I think it can be resolved rather easily. I am writing this post as I solve it for my mac.

basis: Mac OS X is built on unix. I don't have a ready-to-use script, but it shouldn't take more than 5 minutes:

$ sudo du -x -h -d 1 /

You should see where most space is used, in my case /usr and /Users are each consuming more than 60G. /Users are my files that I would clean up later, so I will focus on /usr first.

$ sudo du -x -h -d 1 /usr

And subsequently add subfolders that consume most space. You will reach the root cause pretty quickly with this. My problem was cassandra data and I have moved the commit logs to a different partition, though if I didn't have that choice, I would make Cassandra use an external disk.

If you can't understand where it's used for a folder, just try for example (it wasn't required in my case):

$ ls -lhS /usr/local/var/lib/cassandra/commitlog/

This should work in all cases, and would also work on linux as it always has since a couple of decades ago 😝

Time Machine requires an external drive. Open System Preferences > Time Machine. You can view if it's turned on. I highly suggest you have both a Time Machine and a clone backup.

A LOT of stuff gets included in "System." Notes, reminders, map caches, browser caches and history, SMS, MMS and iMessages, fonts and more all get included in "System." The storage graphic is often wrong. It uses the Spotlight index and when that index gets corrupted the readings are all wrong.

Use Disk Utility to find free space or do a Get Info on your Macintosh HD to find available space.

• Restart in Safe boot mode to clear caches then restart normally.
• Reset Spotlight.

Reset Spotlight in Terminal:

Enter each command followed by <return>

sudo mdutil -a -i off

sudo rm -rf /.Spotlight*

sudo mdutil -a -i on

Depending on the size of your data, this could take some time.

Follow these steps to start up into safe mode.

1. Start or restart your Mac.

2. Immediately after you hear the startup sound, press and hold the Shift key.

3. Release the Shift key when you see the Apple logo appear on the screen.

4. When you get to the login screen, you'll see Safe Boot in red in the top right corner. You don't have to stay in Safe Mode. It's for testing purposes and it clears out certain system caches, amongst other potentially beneficial things. You can either
a. Restart normally
b. Continue to login to test a problem.

More info: https://support.apple.com/en-us/HT201262

Entry level drives are small. It's up to the user to buy a Mac with a drive sized to meet their needs.

The problem is how certain apps save cache files that is causing the problem where you didn't see this in the past. While it's Apple's fault the number is miscategorized, the best option to view your free disk space is in Disk Utility or in a Finder window if you select to view Status bar.

I'm having this problem now as well. 2015 Macbook pro with Sierra. "About this Mac" says system is taking about 111 Gb, but OmniDiskSweeper says all the files on the HD amount to only about 50 gigs, which sounds reasonable since I already deleted almost everything not necessary including iMovie, Garageband and stuff like that.

Caches folder in Library is only about 300Mb.

The only thing that I can think of is the "Private" folder which contains many subfolders that I don't have access to, so neither does OmniDisk. It doesn't even seem to be able to calculate the size for this folders when I click on "get info".

please guys, how can I know how much space these "forbidden" folders take?

Karl Snyder wrote:

My friend has a mid-2012 MacBook Pro with a 750GB hard drive. His storage is almost all system. He doesn't use Photos, iTunes or any other storage gobbling apps. just mainly Word. His HDD is so full I can't even install any type of app cleaner to get rid of files. I didn't get a chance to look at all of his system, but something is causing the computer to fill up the HDD. He's running Sierra 10.12.1.

DON'T install any sort of app "cleaner"!

First, do a full backup.

You should look carefully to see what is using so much space.

You can start by restarting in Safe Mode (it will be slow... that is normal), which will clear some system caches - just in case there is a large one around.

Then restart normally, and do a Finder search for large files - for example, you may do it like the image below.

CAREFUL - do not throw away any files unless you know what they are.

Press command-F in the Finder to search, then choose something like this:

Again, don't just take any file and send it to the trash - be careful only to trash files you are sure you don't need.

And then don't forget to empty the trash.

In my case(1) nether omnidisksweeper nor Disk Inventory X couldn't find the files which take volume.

Also DaisyDisk can find them but they where hidden and there was no access to them. (Access needs Stand-Alone version of DaisyDisk)

(1): My available Storage remains about 90 GB but System size increasing every day.

I've read the responses to this issue and tried the suggestions and something still isn't correct.

I have an early 2015 MacBook Pro with Retina display. I have a 512Gb HD. I partitioned it out with 128Gb for Bootcamp and the remaining 375Gb to macOS 10.13.

When I check storage it shows that it is almost full with about 285Gb being used for System.

I dowloaded OmniDiskSweeper and did a sweep of my Macintosh HD partition and it doesn't add up or show where the System is taking up all this space.

So I'm still in a situation where something is taking up all my available storage and it's not showing.

I've also done the reindexing by adding and removing my Macintosh HD partition in Spotlight and it didn't resolve anything.

I'll continue to do research but this is troubling. Anyhelp would be appreciated... Thanks...

When I look for Time Machine backups in the terminal it shows nothing. I don't have Time Machine enabled as far as I can tell. Still, my system takes up 130GB of 250GB! More than half, and the system is taking up far more space than both Applications and Documents combined!

I have the same problem, I used Disk Inventory X to check what takes up so much space but it doesn't even makes sense, apparently my system takes up 191GB, programs and apps takes almost 11GB.

But when checking with Disk Inventory X it can only find stuff for 91GB, and the biggest thing I have is text documents.

I get the "Storage almost full" warning all the time but I can still download stuff so I guess I still have storage that is free but just not showing.

Instead of checking free space in “About this Mac” "Storage, check in Disk Utility or in the Finder using Get Info on your drive.

About Time Machine local snapshots - Apple Support

Time Machine in macOS High Sierra stores snapshots on every APFS-formatted, all-flash storage device in your Mac or directly connected to your Mac. Time Machine in earlier macOS versions stores snapshots only on the internal startup disk of Mac notebook computers.

To make sure that you have storage space when you need it, snapshots are stored only on disks that have plenty of free space. When storage space gets low, snapshots are automatically deleted, starting with the oldest. That's why Finder and Get Info windows don't include local snapshots in their calculations of the storage space available on a disk.

Do not launch OmniDiskSweeper, use Terminal to run as root. This will get files in system not just Users folder

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

Use command period to quit

It's possible the hidden files are Time Machine backups. Starting with High Sierra, even a desktop Mac creates local snapshots.

How local snapshots use storage space

Time Machine in macOS High Sierra stores snapshots on every APFS-formatted, all-flash storage device in your Mac or directly connected to your Mac. Time Machine in earlier macOS versions stores snapshots only on the internal startup disk of Mac notebook computers.

To make sure that you have storage space when you need it, snapshots are stored only on disks that have plenty of free space. When storage space gets low, snapshots are automatically deleted, starting with the oldest. That's why Finder and Get Info windows don't include local snapshots in their calculations of the storage space available on a disk.

Published Date:Sep 26, 2017

To find all the local timemachine snapshots. Enter this command in the Terminal:

tmutil listlocalsnapshots /

Delete them one by one using

tmutil deletelocalsnapshots <snapshot_date>

This "feature" with APFS + TimeMachine local snapshot is very annoying as time machine will cache whatever you dump into your computer locally on your machine. If you dump 300GB files on your desktop, it WILL cache it in the local snapshot. And it will stay on your computer even after you delete the original file. Yes, you just lost 300GB space even you have already delete the original file.

You will have to manually delete the local snapshot in TimeMachine to get back your space."

https://forums.macrumors.com/threads/high-sierra-wouldnt-remove-320gb-purgeable- space-please-help.2077666/#post-25222356

I've had this happen twice. My first solution was reverting to a Time Machine backup. Obviously not preferable.

Today I had the same issue again, and wound up contacting Apple support. We tried a few different solutions, but the one that ultimately worked for me was re-installing the OS. Now this shouldn't remove your files or applications. As far as I'm aware, it simply re-installs the OS files and clears out the old ones.

1. Reboot your Mac holding cmd+R. You should enter the OS Utilities (disk cleanup, time machine, etc.)
2. One option should be 'Reinstall Mac OS'. Click that and let it run. (You may need an internet connection to download a copy of the OS)
3. Once it's done installing, simply log back in and check your storage space to see if it worked.

I tried the other solutions in this thread, and a few others, but none of them worked for me. Your mileage may vary, but if none of them work for you, give this option a shot.

I had the same problem. Today I used OmniDiskSweeper to take a look and found about 50GB of iPhone backups (from like 6 different iPhones over the years).

Definitely give OmniDiskSweeper a try - it's free. Basically look for big files/directories.

Thanks - had the same issue - used Omnidisksweeper found it in seconds. Probably the same as lots of you... culprit was Parallels - a log file of a crazy 42GB. Deleted and back to normal. Great tip 🙂