The curious case of disappearing storage....

[scotttnz]

Just wondering if anybody has seen this issue and\or known of a resolution?

I have a new 15" MacBook Pro with High Sierra Installed and I noticed that I am rapidly running out of space despite having a 512GB internal SSD and all of documents and photos (other than a small subset that have been imported to the photos app for sharing) living on an external SSD.
On doing some investigation I found that About This Mac is showing a whopping 305GB classified as System, but it doesn't add up. It shows 392.53GB available of 499.31, but if you add up all of the used space it is about 377 used. Get info on the drive shows the "missing" space as Available\purgeable, but About This Mac and terminal do not. I can't create a boot camp partition bigger than 99GB which is how I discovered the problem.

I have chatted with Apple support. First level was typical 1st level, sending me links to articles that I had already seen and tried. Second level was quite good and spent quite a bit of time looking at different things before getting me to reinitialise spotlight. The theory being that it would reclassify whatever it is taking up the extra space as purgeable, and free up the space, but it kind of felt like "oh, try this thing that will run for 2 days so that I can get off this call"
Interestingly the disk space analysis tool he got me to install (Disk Inventory X) doesn't show what is consuming the space. It shows the space as used at the top level, but the analysis doesn't show it.
I kinda feel like it just isn't releasing space from some deleted files. I had a fairly large Parallels vm that I moved to trash and then emptied the trash, but I can't prove that it is related.
So I'm going to let spotlight do it's thing for a couple of days, but does anyone have any other ideas before I erase the drive and reinstall if this doesn't work?

 

[prisstratton]

Maybe take a look at this thread:

https://forums.macrumors.com/threads/solution-reclaim-storage-back-from-system.2073174/

Please give it a read and assess for yourself.

But, ultimately I cannot see it as a solution as it does not stop local TM backups and you cannot get rid of the sleepimage (as far as I can tell).

If you do find something more permanent, please post back and let us all know.

 

[scotttnz]

Maybe take a look at this thread:

https://forums.macrumors.com/threads/solution-reclaim-storage-back-from-system.2073174/

Please give it a read and assess for yourself.

But, ultimately I cannot see it as a solution as it does not stop local TM backups and you cannot get rid of the sleepimage (as far as I can tell).

If you do find something more permanent, please post back and let us all know.

Thank you so much!! I have done so many searches today looking for a fix, but hadn't found that thread. About This Mac System space has gone from 305GB to 34GB after running the commands in that thread. I have passed the info on to person I was dealing with at Apple support, hopefully it will get to somebody who can make it better.

 

[Significant1]

There is no reason to disable local snapshots, as it is considered available 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."
https://support.apple.com/en-us/HT204015

So I would consider it a bad advise to disable it, unless there is an actual problem.

 

[scotttnz]

There is no reason to disable local snapshots, as it is considered available 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."
https://support.apple.com/en-us/HT204015

So I would consider it a bad advise to disable it, unless there is an actual problem.

There was an actual problem. I was unable to create a boot camp partition because there was not enough available space. I have no problem with the system using available space for that sort of background process, as long as it is available to use when I need it. In this case it wasn’t.

 

[Significant1]

There was an actual problem. I was unable to create a boot camp partition because there was not enough available space. I have no problem with the system using available space for that sort of background process, as long as it is available to use when I need it. In this case it wasn’t.

Ok, maybe that should be considered an error in the boot camp-assistant app (which Apple perhaps should be made aware of), because in my opinion it should also consider the space available

 

[scotttnz]

Ok, maybe that should be considered an error in the boot camp-assistant app (which Apple perhaps should be made aware of), because in my opinion it should also consider the space available

I don't know if I would have been able to write data to the drive and space would have been made available or not. I still had about 100GB free, so would have had to write a lot of data to test that. But I do want to create a 150GB boot camp partition which I was unable to do, but can now. I have advised the 2nd level Apple support person I was dealing with, so hopefully he will tell somebody who can do something about it.

 

[Weaselboy]

There is no reason to disable local snapshots, as it is considered available space:

There does not appear to be a way to disable them under HS anyway, unless you just turn off Time Machine.