Differing Used HD Space Reports in OS X

November 15, 2013 8:54 AM

According to Disk Utility, I have only 36 GB / 500 GB free, and it's been pretty full for a while. For the last year I've taken this at face value, but today I looked into it closer, and found that according to other applications (Disk Inventory X and JDiskReport), I apparently should have more like 200 GB free. How can I figure out what is using this extra space?

I'm using a 2012 Macbook Pro, running the latest version of Mavericks, with everything updated. Under "About This Mac", it shows that ~218 GB are being used as "Other", but I believe that Disk Inventory X and JDiskReport are not showing this space at all. I also made sure that both applications were scanning my full hard drive.

I've never used Time Machine, so I don't think it's saving backups anywhere. According to Disk Inventory X, my sleepimage is ~4 GB and swapfile is ~1 GB, so I don't think this is contributing. I also have never installed a partition on this hard drive. Because my reported free space has been hovering around 50 GB or so for the last year, I don't think it's related to the Mavericks update or anything recent. I also run Cocktail every week to clear logs, etc.

Here's a screenshot showing the different reports.

Is there something I'm missing? What could be this "Other" that's taking up so much space? Is there a way I can access this "free space", or do I just need to wipe the drive and start from scratch?

posted by Yiggs to Technology (20 answers total)

Do you use Time Machine to make backups? This thread suggests disabling local snapshots (specifically, on Mac portables, like the MBP you use) to get the Finder to make a more accurate calculation of free disk space.
posted by Blazecock Pileon at 9:08 AM on November 15, 2013

Have you emptied your trash? MacOS' default tools (Info page, Disk Utility) don't report the space in the Trash as available.
posted by Nelson at 9:09 AM on November 15, 2013

Try emptying the trash folder, if you haven't ever/recently done that.
posted by skewed at 9:09 AM on November 15, 2013

I recommend the much easier to parse application WhatSize.

If you're seeing an incorrect amount reported that could be corruption that can be fixed with Disk Utility or DiskWarrior.
posted by ridogi at 9:10 AM on November 15, 2013

Oh and if you want yet another tool for reclaiming Mac disk space, I really like DaisyDisk. Worth the $10, but you can use the free version for reports and just delete stuff via Finder yourself.
posted by Nelson at 9:11 AM on November 15, 2013

I think you're going about this the right way, and don't necessarily think you need to install anything different right now. You should know what files are the taking up the most space on your computer before you do anything drastic like reformatting the hard drive and reinstalling the operating system.

In the JDiskReport, look at the files instead of looking at the directories. Of course /Users is going to have the most stuff, but we can't see what those things are. Also, what does the Top 50 list show?
posted by oceanjesse at 9:12 AM on November 15, 2013

Best answer: Grand Perspective is an awesome app to quickly see who is hogging all of your disk space.
posted by JoeZydeco at 9:32 AM on November 15, 2013 [1 favorite]

Seconding Grand Perspective. It's a perfect tool for this exact problem.
posted by tylerkaraszewski at 9:52 AM on November 15, 2013

Grand Perspective is awesome and I find it really fun.
posted by OmieWise at 9:56 AM on November 15, 2013

Response by poster: The trash is empty - in fact, I compulsively empty it whenever I notice it is full, which ends up being 4-5 times a day.

I scanned with Grand Perspective, and got the following results:
Volume size: 464 GB
Size of scanned files: 294 GB
Miscellaneous used space: 136 GB
Initial Free Space: 33.5 GB

This seems in line with the 218 GB of mystery "Other" space used shown in Disk Utility.

I also ran DaisyDisk, and I get ~295 GB used space, but I also get 150 GB of "hidden space". It says this is taken by restricted and system files, and needs to be rescanned as an administrator to see. However, I am the administrator - I only have one user account on this computer and it has full administrator rights.

What could this "hidden" or "miscellaneous" used space be? And more importantly, how can I free it up?
posted by Yiggs at 10:13 AM on November 15, 2013

Do you use Time Machine to make backups?
posted by Blazecock Pileon at 10:35 AM on November 15, 2013

Best answer: DaisyDisk has a menu option for "Scan as Administrator". It's under the little down arrow to the right of the usual Scan button.

Time Machine is the next-best guess after the Trash. On laptops Time Machine will back up to the laptop hard drive until you plug in your USB backup drive.
posted by Nelson at 10:38 AM on November 15, 2013

Response by poster: Time Machine is off, and I haven't ever used it on this computer, so I don't think it has made any backups.

I scanned using DaisyDisk again as an administrator, and now it says 150 GB is "hidden space" that is "unable to be located." It says this space is "not accessible to users."

Any ideas?
posted by Yiggs at 10:53 AM on November 15, 2013

http://whatsizemac.com will show the space used by versioning
posted by Lanark at 11:35 AM on November 15, 2013

Best answer: If you haven't already, I'd comb through Apple Support and see how others are solving this problem. Like here's a discussion from 2010 with almost exactly the same problem.

Some of the possibilties here include corrupted Time Machine files sitting in root that can't be automatically deleted.
posted by JoeZydeco at 12:05 PM on November 15, 2013

The app I mentioned above is going to show all files and is well worth the ~$12 it costs, and sorts by size rather than a pie chart or other useless graphic so biggest folders are at the top, and clicking on a folder shows the breakdown for that folder so you can drill down to the problem.

You can also look with terminal to see what is using space. For example this will show you all folders at root level:

sudo du -sh /*

You could dive into a particular folder with the path. For example to see your user folders usage:

sudo du -sh /Users/yourusername/*
posted by ridogi at 12:43 PM on November 15, 2013

Grand Perspective should also be run as root from the / directory to get a better idea of what's going on.
posted by JoeZydeco at 12:48 PM on November 15, 2013

Response by poster: Following the link from JoeZydeco, I found this site which recommended the following command in Terminal: "sudo du -cxhd 1 /"

This gave a list of used space similar to the other programs, but it included 131 GB in /.DocumentRevisions-V100!

Doing a bit more reading, it looks like this is where OS X (I guess after Mountain Lion?) stores autosaved files. I have no idea how it got so big, or why more people don't have this problem.

Anyway, I make my own backups and don't need this feature, so I deleted it with "sudo rm -r .DocumentRevisions-V100". Now I have 176 GB free! I'll look into disabling this permanently, but in the meantime I guess I'll just have to manually delete it every so often.

Thanks for the help!
posted by Yiggs at 12:59 PM on November 15, 2013 [1 favorite]

I was going to offer up "du" as the best option. For those of you who might care after the fact, a translation of "sudo du -cxhd 1 /":

sudo -> do as super user, i.e., allow access to administrative stuff
du -> disk usage
-c -> Display a grand total.
-x -> File system mount points are not traversed. (Just stay on this disk, ignore other disks.)
-h -> "Human-readable" output. GB rather than bytes.
-d 1 -> Traverse to this depth (1 level down, in this case).
/ -> start at the top level, the root directory. That needs admin access, hence "sudo".

All of this is easy to access via Terminal: just type in "man du" to get the man(ual) page for du.
posted by RedOrGreen at 3:17 PM on November 15, 2013

Use Disk Utility to repair the system disk if you haven't already done so. Too late now, but just deleting system directories is not generally a good idea.

DocumentRevisions-V100 stores previous versions of documents which are auto saved. There is a preferences setting (in General) which turns off auto save, applications which want to use this feature will then prompt you, this might help. Auto save seems to have no other management controls, especially not a "keep last n versions" setting.

That seems like a lot of disc space though, my biggest is 12Mb. Did you have an image or video editor which you deleted or stopped using? Also check if the DocumentRevisions folder is backed up by time machine and remove it from there as well (exclude from future backups then delete from time machine).
posted by epo at 3:44 AM on November 16, 2013