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ben1969

macrumors member
Original poster
Mar 18, 2008
67
0
I just did a SuperDuper backup of my system drive. It backed up fine at about 308gb. I checked the backup by booting from it, then rebooted and spent the day working on my system. I was trashing a few files and just noticed that the finder indicates that my system is using up nearly 545gb. I ran Baseline and what's weird is that Baseline finds these values (system, 4gb; applications, 14gb; library, 20gb; users, 230gb ; plus other misc files -- for a total of 270gb) but also shows that the amount of space the system disk is taking up is also 545gb. Where is this hidden space being taken up? It looks like the actual files on the disk are being doubled and read as twice their true values. Anyone ever have a problem like this?
 
Quite a bit of the OS is hidden from view. Use OmniDiskSweeper to see what size everything is on your Mac. Word to the wise though, don't start nuking stuff without knowing what you're nuking first.

Alternatively:

sudo du -h -d1 /

Will also help lead you to the culprit(s).
 
@yellow

Thanks, I'm downloading ODS now. What's weird to me is that it's double the size of what my hd should be. For 270gb to be hidden would be remarkable.
 
Again, weird

With OmniDiskSweeper I get the same smaller results (about 270gb total), but the finder still shows about 540gb of space used on the disk.
 
Hmm

@DualShock
Trash emptied and DiskUtility ran (repaired permissions, verified disk).

@Yellow

Ran Terminal and got this...

2.0M /.fseventsd
283M /.Spotlight-V100
0B /.TemporaryItems
0B /.Trashes
14G /Applications
3.9M /bin
0B /cores
du: Can't follow symlink cycle from /dev/fd/3 to /dev/fd/3

Googling this now, but does it make any sense to you? Thanks in advance for any help you could offer.
 
@DualShock
Trash emptied and DiskUtility ran (repaired permissions, verified disk).

@Yellow

Ran Terminal and got this...

2.0M /.fseventsd
283M /.Spotlight-V100
0B /.TemporaryItems
0B /.Trashes
14G /Applications
3.9M /bin
0B /cores
du: Can't follow symlink cycle from /dev/fd/3 to /dev/fd/3

Googling this now, but does it make any sense to you? Thanks in advance for any help you could offer.

You're.... you're missing quite a few folders there in the output. Didn't think a cyclic symlink would stop the du command though...
 
@Vylen

Yeah -- I'm seeing similar problems on a quick google search.

Just ran GrandPerspective and it shows that the size of scanned files is about 270gb and the size of "Miscellaneous used space" is also about 270gb.

What is this "Miscellaneous used space"?
 
Yeah -- I'm seeing similar problems on a quick google search.

Just ran GrandPerspective and it shows that the size of scanned files is about 270gb and the size of "Miscellaneous used space" is also about 270gb.

What is this "Miscellaneous used space"?

No idea... stuff the application can't categorise? Actually, I think you can google what it means...

Anyway, try run this in terminal

sudo /bin/bash -c "for dir in \`ls /\`; do du -sh /\"\$dir\"; done"

Essentially, it runs the du command on the individual folders and files in the root directory of your drive. This means that the error with going through /dev/ wont effect anything. And well, parsing /dev/ is unimportant anyway - don't need to know the size of it.
 
@Vylen

No idea... stuff the application can't categorise? Actually, I think you can google what it means...

Anyway, try run this in terminal

sudo /bin/bash -c "for dir in \`ls /\`; do du -sh /\"\$dir\"; done"

Essentially, it runs the du command on the individual folders and files in the root directory of your drive. This means that the error with going through /dev/ wont effect anything. And well, parsing /dev/ is unimportant anyway - don't need to know the size of it.

Thanks -- I'm at work now, but will try this when I get home this pm. My quick google search this am seemed to show a few other folks having a similar problem with phantom disk space being shown in finder, but not being accurately reflected when the disk was being inspected more closely.
 
IIRC, you won't see cumulative totals for Users' directories that you aren't the owner of (even if you are an admin user - 'sudo' should work around this).

Good luck finding the phantom! :eek:
 
I too am surprised that du wasn't able to skip /dev irregularities. You did use 'sudo' right?

Stopping due to the irregularities with /dev/fd/3 should be normal since it can't continue it's purpose in accurately determing disk usage with an unresolved cyclic symlink - doesn't matter if he runs as root or not.

P.S Yes, I know I said I was surprised earlier, but, I thought about it for a bit after posting and it made sense to me :p
 
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Update

Here's what I got from running @Vylen's latest tip...

Last login: Thu Jan 20 06:15:46 on ttys000
MP-Home-1TB:~ macprohome$ sudo /bin/bash -c "for dir in \`ls /\`; do du -sh /\"\$dir\"; done"
Password:
24K /.DS_Store
24K /.DS_Store
du: /(from: No such file or directory
du: /old: No such file or directory
du: /Mac): No such file or directory
287M /.Spotlight-V100
0B /.TemporaryItems
0B /.Trashes
4.0K /.apdisk
du: /.com.apple.timemachine.supported: No such file or directory
du: /(from: No such file or directory
du: /old: No such file or directory
du: /Mac): No such file or directory
0B /.file
2.1M /.fseventsd
128K /.hotfiles.btree

14G /Applications
20G /Library
0B /Network
2.5G /System
du: /User: No such file or directory
du: /Guides: No such file or directory
du: /And: No such file or directory
du: /Information: No such file or directory
244G /Users
3.7T /Volumes
3.9M /bin
4.0K /com.brother.ControlCenter.plist
0B /cores
du: Can't follow symlink cycle from /dev/fd/3 to /dev/fd/3
4.0K /etc
1.0K /home
1.0K /home
du: /(from: No such file or directory
du: /old: No such file or directory
du: /Mac): No such file or directory
18M /mach_kernel
1.0K /net
1.3G /private
2.7M /sbin
4.0K /tmp
501M /usr
4.0K /var
MP-Home-1TB:~ macprohome$
MP-Home-1TB:~ macprohome$

This looks like 260gb, total. Still seeing about double this amount in the finder as used space on the disk. Will start to hunt a bit more for an answer, and will post if I find anything.
 
Bah, stupid me, I should've checked that it worked properly before... that's what I get for writing a bash script after midnight.

This here will check all the subdirectories and files in the root directory, but not the ones that are preceded by a . (which should be fine since the previous command did it)

sudo /bin/bash -c "for dir in /*; do du -sh \"\$dir\"; done"

But, I don't think you really need to run it. Like DualShock asked...

Do a sudo du -sh "/home (from old Mac)"

[EDIT] edited command based on below post.(PS good catch)
 
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What's in the "(from old Mac)" directory?

or is that two directories?

One called "home" (1k)

and one called "home (from old Mac)"

:confused:

EDIT: I'm going to go out on a limb here, but I would suggest unmounting and disconnecting ANY external drives you have (going by "3.7T /Volumes" in the previous output), and re-running the previous command.

What I'm most concerned about here is that a FOLDER has been generated in the /Volumes directory that matches the name of one of your external drives. :eek:

for reference: http://db.tidbits.com/article/9620

@Vylen: cheers! :)

EDIT 2: I'm not to certain that if there IS a folder of the same name as an external, that you should simply delete it. It probably will be data that is NOT duplicated.
 
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Update...and maybe a clue

Swamped with children, but back to trying to figure this out.

@DualShock and Vylen -- here's what I got...
Last login: Thu Jan 20 21:56:10 on console
MP-Home-1TB:~ macprohome$ sudo du -sh "/home (from old Mac)"
Password:
0B /home (from old Mac)
MP-Home-1TB:~ macprohome$

and


MP-Home-1TB:~ macprohome$ sudo /bin/bash -c "for dir in /*; do du -sh \"\$dir\"; done"
14G /Applications
20G /Library
0B /Network
2.5G /System
4.0K /User Guides And Information
245G /Users
3.2T /Volumes
3.9M /bin
4.0K /com.brother.ControlCenter.plist
0B /cores
du: Can't follow symlink cycle from /dev/fd/3 to /dev/fd/3
4.0K /etc
1.0K /home
0B /home (from old Mac)
18M /mach_kernel
1.0K /net
1.3G /private
2.7M /sbin
4.0K /tmp
501M /usr
4.0K /var
MP-Home-1TB:~ macprohome$

To explain the volumes it might help to know my drive setup:
3x2TB (2TB Media, a 2TB backup of the Media files, and a relatively empty 2TB drive which will be for new media files)
1x1TB (my system drive, apps, itunes, iphoto)
1x640gb (my old system drive,

In looking at the Grandperspective scan, I can see via the entire volume view the 1TB drive split into nearly three equal pieces -- the files I expect to be there, broken down into different colors, a large black square of free space, and a gray space of "miscellaneous used space." (I've attached a screenshot, I think).

One clue that I think might explain the missing space is that I have just switched my system/apps/user files for my 640gb to the 1tb drive. I used to use the 1tb as my TimeMachine drive for the system/apps/user files. Is it possible that this "miscellaneous used space" is the TimeMachine backup that should have been erased when I reformatted the drive?

I'm doing more digging and will post anything I find. Thanks to all who have posted advice.
 

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Solution?

Upon further digging, what I have appears to be exactly what is described in the article MacTech68 linked (thanks!) -- a hidden Volume that, if I understand it, was created on my 1tb drive when I did not properly eject/dismount an external backup.

I've tried to trash the volume in Omnidiskwweeper, but it somehow rebuilds itself. Working on getting this done now.
 
To see if you have an "un-real volume" problem.

Un-mount AND disconnect all your external drives.

In the finder, click on the "Go" menu in the menu bar, and select "Go to folder".

In the box that opens, type:

/Volumes

an click "Go".

In the window that opens, if you see a folder of any name, drag it to the desktop.

The /Volumes directory should only ever have Alias or symbolic links (shortcut files) to your volumes, NEVER an actual folder.

When a drive mounts, an alias to that volume is automatically placed in the /Volumes directory of your boot drive and is normal.
 
Thanks -this was my issue (a volume properly belonging to an external drive that was remounted onto my system hard drive after the external drive was apparently improperly disconnected). My problem now is that after having put the offending volume into the trash, I am not able to empty the trash. Doing so should free up the "miscellaneous used space." I've tried just about everything I can think of (forcing won't work, TrashIt won't work). The Trash "get into" shows that its size is 270gb, but no files or volumes are visible. Any ideas?

Thanks, again. I was able to finally delete the volume by running sudo rm -rf ~/.Trash via Terminal. Finder now indicates the proper size of the hard drive. Have I deleted the Trash (trashed the Trash)? Do I just need to reboot? I tried mkdir ~/.Trash but am told by Terminal that .Trash already exists.
 
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Damn, I just had this happen to me this past week with the SSD in my MBP. It was a complete mystery. I couldn't locate the source of the "hidden" occupied space, and ended up repartitioning and restoring the SSD. That cost me time but nothing else.

At the time I thought maybe the SSD controller went flakey on me, but this makes perfect sense. Just before it happened I was doing a SuperDuper backup, and the ext drive very briefly unmounted and then remounted.

Now I know what the problem was and know what to look for the next time. Weird though that none of the shell or GUI disk/file utilities could reveal to me what was going on.
 
@RaceTripper

Indeed, it was a very weird issue, and I'm just glad that the Terminal experts here are so generous with their time and expertise. The article that MacTech68 hyperlinked above is definitely worth reading.

As for the utilities, Grandperspective and OmniDiskSweeper definitely helped by letting me "see" the space that was missing. Getting to that Volume and trashing it absolutely required using Terminal. I was a bit nervous, having never really done much with Terminal, but it really was impressive what you can do if you know (or, at least others know) what to do.

Thanks again to all those who offered help. I really appreciate it.
 
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