11 Replies Latest reply: Feb 28, 2012 6:28 AM by g_wolfman
GoldenPRGuy Level 1 (0 points)

I often add very large files to my system before compressing them, sending them to clients, and then deleting them. This process leaves me constantly thinking about how much disk space I have free. Disk Utility, and an Apple approved app called DaisyDisk (space visualization) typically help me accompish this. Sadly, as of this week I seem to have a problem. When I went and looked the other day Disk U was telling me that 250gb of my 320gb drive is in use. This seemed high to me, but to be safe I thought I'd delete some files I didn't need. After deleting a bunch of videos, and a backup of my Main Identity (19gb) from my system, I'd assumed I had freed up about 24gb, but when I went back into Disk U it was still showing the same 250gb in use. Yes I rebooted my system, and made sure the trash was empty. As I investigated further I did a get info on all 6 folders on the MacHD and they added up to about 170gb. That seemed more realistic, so I did a get info on my MacHD and again it showed the same thing 170 in use and 148.something available. Note: I have no partitions on this drive. But yet, still when I go to Disk U it seemed to be stuck at only 64gb free. Today when I went and looked again I am still seeing the same amount in use and free on the MacHD get info, but on Disk U now I am seeing 108 free and 211 in use. Why the difference? I would think Get Info was pulling from the same place as the mac disk utility.


Would appreciate any insight!



MacBook Pro 15", Mac OS X (10.4.7)
  • HACKINT0SH Level 5 (5,760 points)

    There are other items at bay which can fudge up the numbers. For example Time Machine is often to blame, as it stores hidden snap shots on your drive, etc.

  • GoldenPRGuy Level 1 (0 points)

    Thanks for the reply Hackint0sh, but even if you're correct and there are hidden temp files, it's not like I am adding up only the things I can see. The system's disk space used or free should not vary regardless of what is visable and what is not. A temp file is still a file. If for some reason I was looking one day, and then again the next and the numbers were different, ok you'd have a point, the temp file might have been purged once time machine completed a backup, but I am talking about right now at the same exact time. Here is the reading on both right now: Get Info on MacHD = 148.71gb Free, and Disk Utility on the same MacHD = 107.86gb Free. I think that's messed up.

  • fane_j Level 4 (3,660 points)

    GoldenPRGuy wrote:


    I think that's messed up.

    The first thing you need to do if you believe something is 'messed up' is to verify your disk. Incorrect reporting of free disk space is often a symptomp of directory corruption. So, before discussing this any further, Verify Disk and then we'll talk some more.

  • macjack Level 9 (51,639 points)

    TryWhatSize or OmniDisksweeper can help you find what's hogging your disk space.

  • GoldenPRGuy Level 1 (0 points)

    Fane_j: Thank you for your verify suggestion. I've torn through MBP's so quickly these past few years that I have never had to run one. Suffice it to say, I did, and there were a number of problems, so I did a reboot command R, and ran repair HD. It apparently fixed everything. Sadly the space issue still exists.


    Disk U on MacHD:

    Capacity: 319.21 gb

    Available: 117.41 gb

    Used: 201.8 gb


    Get Info on MacHD:

    Capacity: 319.21 gb

    Available: 158.79 gb

    Used: 160.43 gb


    I am really trying to get to the bottom of that discrepancy. Any more thoughts?



  • GoldenPRGuy Level 1 (0 points)

    Thanks macjack, I am familiar with the program. It is similar to one I use called DaisyDisk that I bought from the macapp store. They are great for identifing larger files that can be deleted, but not for helping me get to the bottom of this free space discrepancy. From what I have seen programs like this model Disk Utility in their readings (identically actually), but both fail to explain where 50GB seems to have disappeared to.



  • fane_j Level 4 (3,660 points)

    GoldenPRGuy wrote:


    Any more thoughts?

    (1) What version of the OS are you using? Your OP says 10.4.7, but you're posting in the 10.6 forum.


    (2) In Terminal, what does


    df -H



  • jsd2 Level 5 (6,200 points)

    I did a reboot command R


    Command R?? Are you running Lion?

    Your profile shows OS X 10.4.7 Tiger, and you have posted in the Snow Leopard forum.  If you are indeed running Lion, then see

    OS X Lion: About Time Machine's "local snapshots" on portable Macs


    which includes:


    Note: You may notice a difference in available space statistics between Disk Utility, Finder, and Get Info inspectors. This is expected and can be safely ignored. The Finder displays the available space on the disk without accounting for the local snapshots, because local snapshots will surrender their disk space if needed.


  • GoldenPRGuy Level 1 (0 points)

    fane_j, again thanks for the heads up on the dated profile ...  it's fixed now.


    1) I am running Lion, and not sure how or why I posted in the snow leopard category.

    2) It says:

    Filesystem                                Size   Used  Avail Capacity  Mounted on

    /dev/disk0s2                              319G   202G   117G    64%    /

    devfs                                     210k   210k     0B   100%    /dev

    map -hosts                                  0B     0B     0B   100%    /net

    map auto_home                               0B     0B     0B   100%    /home

    localhost:/41KishPaycOkx6AG3BUu4C         319G   319G     0B   100%    /Volumes/MobileBackups

    /dev/disk2s6                              750G   727G    23G    97%    /Volumes/Time

  • GoldenPRGuy Level 1 (0 points)

    This is what I was looking for jsd2! Thank you! And as your note says, there is about 45gb under "backups"! Perfect!


    Thanks so much to everyone who replied. Super helpful!

  • g_wolfman Level 4 (1,120 points)

    The version of DaisyDisk available on the Mac App Store is subject to limitations (as are all App Store apps) that forbid it from running as an administrator.  That means it cannot access any of the hard drive not under your user ID's control and that some of the information returned to it by low level processes may be "filtered" (for lack of a better term).


    I haven't looked at their page on the App Store recently, but I believe they were fairly explicit about pointing out these limitations.  They sell a non-App Store version that can run in administrator mode and see everything on a drive.  That's the version I use.


    Since most free space issues involve OS processes (like the aforementioned Time Machine local snapshots) its not surprising you can't resolve them using an App Store application.