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

My friend did the safe boot and then rebooted. He said initially he gained back several gigs of HDD space but the system files just growing again. Very perplexing. I will try a search for large files. As I’ve mentioned he doesn’t have any video, audio or photos on the computer. I may have him boot into recovery mode and reinstall. He doesn’t have any way to back up his computer.

I have a brand new late 2016 non touch bar MacBook Pro, after clearing it of all unnecessary programs and installing, logic, MainStage, pro tools, Ableton, and some other programs my system folder now measures 136gb. This makes zero sense. 136gb of a 250gb macbook using system files that can't be accessed by clicking on "manage" under about this Mac.

There are many reasons the System files can be that large. You might have to explore to make the determiniation as to which are not needed.

System files include things like the Apps, all the back up files and including the files for syncing across multiple devices.

Lest we forget, it is also where al ot of the internet bloatware is stored.

when you go to the apple logo in the top left corner, click on it and then go to 'about this mac' and then go to "storage " and there you will see "manage" button. Please click on that and then you will be able to see that how much storage is each and everything taking...

I am facing the same problem. I just bought a new 2017 macbook air new model with 128gb ssd and let me tell you, when I was in sierra, the system was taking around 6-7 gb but now it is taking around 38gb in high sierra and it keeps getting increase. I have found that whenever I delete anything on my mac and then empty my trash, the storage of the trash gets added to the system files. for example- if I have my system files of 38gb now and my trash has 500mb of files, by emptying the trash, this 500mb will get added to 38gb and will become 38.5gb and nothing will increase in the free space.

I have also contacted apple care and have talked to the senior advisors and they have asked for a 4 days time to consult their engineering team and then they will reply to me on 3 October,2017.

please reply to me if anyone has this same problem.

There are several apps that can save to Storage. See this post about local Time Machine backups taking up space.

https://forums.macrumors.com/threads/solution-reclaim-storage-back-from-system.2 073174/Solution: Reclaim storage back from "System" | MacRumors Forums

128GB of storage is quite small, but this doesn't mean 50GB of storage taken from the system is normal.

I reckon there is something in your OS which is filling up the SSD. You said you wiped it clean and installed macOS High Sierra from scratch, didn't you? This means the new OS was basically empty, except for Apple's software.

I would suggest to use apps either like DaisyDisk (extremely user friendly), or OmniDiskSweeper, to check where those files are located and what are they.

Have you got a Time Machine backup enabled? The files might be Time Machine local snapshots.

Otherwise, they could be temporary files. If this is the case, you should simply shut down the computer. Once you start it up again, they might have gone.

I think I know what it is. Under sharing I found this new option called content caching. That cashes things from your network to speed up downloads. It's not a good idea to use that on laptops. I never turned it on. But try turning it off and see if it helps.

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

command period to quit

How did this affect your applications and settings that were installed before you re-installed the OS? I have applications like Microsoft Office installed and have many complex rules in Outlook that would take a lot of time to rebuild and would like to avoid it if possible.

Removing the time machine backups.

I did the OmniDiskSweeper both launching the application and through the terminal via sudo and the results were the same and both did not show the TimeMachine backps.

I followed the instructions regarding removing the TimeMachine backups and deleted one snapshot as a test and it worked so I cleared the remaining items. I was confident that I had a recent backup completed. I would probably suggest or encourage a backup is complete before manually deleting the snapshots just in case.

I spent over an hour chatting with support about having over 300GB in system storage. They tested many things but after the chat I found that the system was still recognizing my old MacBook via iCloud. You can edit devices under system preferences. Once I deleted my old laptop the problem was solved.

I had the same problem, but was not using Time Machine and verified I had no local backups using the command line listed in one of the other replies. My System files were taking up 115 GB of disk space, using High Sierra MacOS 10.13.2. I fixed the problem by installing the free app Dr. Cleaner from the App Store. After launching its, it immediately saw 101 GB in junk files, and cleaned them in less than a minute. Now my System file usage is 14 GB.

branko888 wrote:

I had the same problem, but was not using Time Machine and verified I had no local backups using the command line listed in one of the other replies. My System files were taking up 115 GB of disk space, using High Sierra MacOS 10.13.2. I fixed the problem by installing the free app Dr. Cleaner from the App Store. After launching its, it immediately saw 101 GB in junk files, and cleaned them in less than a minute. Now my System file usage is 14 GB.

Ouch!!! Cleaners are trouble. Here's hoping it doesn't come back to bite you.

I searched and searched and found this and it worked.

If you are on High Sierra then… it's TimeMachine fault.

That's the solution that worked for me.

Type this command in you terminal:

sudo tmutil listlocalsnapshots /

to check the snapshots of TimeMachine. You get some strings like these:

com.apple.TimeMachine.2017-10-02-132639 com.apple.TimeMachine.2017-10-02-175507 com.apple.TimeMachine.2017-10-02-200417 com.apple.TimeMachine.2017-10-02-235853 com.apple.TimeMachine.2017-10-03-112713 com.apple.TimeMachine.2017-10-03-112934 com.apple.TimeMachine.2017-10-03-113254

You need this command to delete TimeMachine mess:

tmutil deletelocalsnapshots 2017-09-27-112934

Type a command like this for each of those snapshots and you'll get a great amount of free space!