Previous 1 2 Next 16 Replies Latest reply: Dec 13, 2012 6:40 PM by knarfrh60
knarfrh60 Level 1 Level 1 (0 points)

I have a 1TB iMac and have two external hard drives attached to keep the computer free of hard drive use for two reasons: Disk 1-is a 250GB hard drive I have dedicated to perform Time Machine backups of my home folder. Disk 2-is a smaller 120GB hard drive I keep my compete iTunes library of music in case the computer has a malfunction, so all the work I've done putting the library together will be secure. Here's the thing...the iMac's hard drive is hardly used, just as I want containing about 150GB total.  Meanwhile, the Time Machine disk is nearly full with  225GB used, and just 25GB remainibg. The hard drive with the iTunes files looks pretty good too using about 70GB of it's 120GB.  I believe Time Machine is in no way, backups the iTunes library just the iMac.


How can I figure out where the additional space is getting used up on that disk?  I do have a couple of extra logins I use for alternate use such as a different iPhoto library I want kept seperate from mine, but I did not think the backup was saving those files as they are not even under the Time Machine setup.


Can anyone advise why the backup is larger than the use of the computer?  I knew when I dedicated a smaller hard drive to back up a larger one that it was possible the backup drive would get too full, but I can figure out what's happening. I've erased the Time Machine disk and allowed it do a completlely new backup and again, it's always sigificantly larger.



iMac, Mac OS X (10.7.3), iMac 21.5" Intel Core Duo 3.06 Ghz
  • BDAqua Level 10 Level 10 (121,165 points)

    Where do you see the 150 GB total for your internal drive?


    How much free space is on the HD, where has all the space gone?


    OmniDiskSweeper is likely the easiest/best, and is now free...



    And if needed, you can use Terminal to run it in admin mode to see files/folders your user can't see...


  • knarfrh60 Level 1 Level 1 (0 points)

    To obtain information on all three hard drives use I just Apple "I" it to Get Information about that particular disk. Which of the three disks do you want to know the free space?


    iMac disk - 159GB used, 840GB available

    Time Machine disk 226GB used, 23GB available

    iTunes disk  68GB used, 51GB available


    Should I follow one of those links?

  • BDAqua Level 10 Level 10 (121,165 points)

    Hmmmm, Did you check the 250 when it was blank?


    Have you verified the drives in Disk Utility yet?

  • knarfrh60 Level 1 Level 1 (0 points)

    I just ran Disk Utility and it says all is fine. I believe I did check the 250 when it was blank by seeing it's available space with Get Info, but that was all that I did.  I'll try using the utilty and terminal procedure you advised earlier, and see what we have.

  • knarfrh60 Level 1 Level 1 (0 points)

    I also wanted you to know I posted back in June trying to resolve issue under the discussion listed:


    "How can I change time machine settings? "

  • BDAqua Level 10 Level 10 (121,165 points)

    Well, we'll try to get to the bottom of it.


    Did that other question ever get resolved?

  • knarfrh60 Level 1 Level 1 (0 points)

    Not really.  Back in June I was given advice on how to use the Time Machine software I have used on two different Apple computer without any confusion using it's simple interface. I may have erased the 250GB at that time and did the fresh backup...I don't remember.


    Right now, I'm trying the first run of OmniDiskSweeper without using Terminal from the Finder / iMac.  The 120GB information was identical.  Currently, it's working on the 250GB processing / sizing.

  • knarfrh60 Level 1 Level 1 (0 points)

    Okay here's the results from running OmniDisk from the Finder on the iMac:


    120GB/iTunes Drive:

    68.2GB for the iTunes folder and all the remaining items are small-between 6MB to 536KB


    250GB/Time Machine Drive:

    7.0TB for Backups folder and remaining items again are even smaller 800KB to 4KB



    95GB Users

    26GB Library

    15GB Applications

    4GB System

    1MB private

    600MB usr

    175MB System Folder and then again, the remaining items run smaller ranging from 15MB down to 4KB


    I didn't make any deletions, but I did screen shots for all the information. I believe I may not have gone far enough into it's interface and information to obtain detailed info. One thing that is somehow wrong is the figure of 7.0TB on the 250GB Time Machine Drive, which by the way was the only disk which took a very long time.  Can you see anything sticking too that may be an issue?

  • BDAqua Level 10 Level 10 (121,165 points)

    Something really messed up on the 250 GB drive, can you afford to erase it & do a one pass Zeroing?

  • knarfrh60 Level 1 Level 1 (0 points)

    Yeah - sure I was already preparing to do that and to my surprise, the iTunes Disk had not been excluded from Time Machine.  We may have figured it out.  Thanks. I'll get back to you on these results.

  • knarfrh60 Level 1 Level 1 (0 points)

    Okay...I have some more information and perhaps we are getting closer.  On the 250GB, first I went into that disk and used Disk Utilty to re-format it once using Mac OS Extended (Journaled) then a second time, zeroing it out. I did a screen shot to review if needed, and both times it looked perfect...249GB available.  Then I went into the Time Machine preferences to get ready to backup again, and it had not excluded the other external 120GB with iTunes so I excluded it. I may has previously, never noticed in that screen that it takes a bit of time for it to calculate the information to save.  I may have just clicked on it quickly without reviewing it first.  Today I did, and gave it time to calculate.  At one point the actual 250GB itself, showed up and I excluded it too like the 120GB.  After it finished, the calculations are still it wrong - claiming it has a 200GB backup when the iMac either contains 150GB (based on when I do Get Info) on it or from OmniDisk which calculated about 100GB.  I have not allowed Time Machine to do a backup yet, until this discrepancy can be clear.


    One thing that I thought I had seen or reviewed previous on the Time Machine settings was my home folder - I could be wrong but wanted to mention that.  Another little tidbit to ponder an well is that I have a files of icons that I use for the Hard Disks, and a few folders where I Get Info on the Icon and on the destination and just cut and paste.  I did that today to the 250GB after zeroing, but while I was in the Time Machine settings the change was deleted and neither the manufactures icon was there nor mine, and it has the default blue-green one the software uses.  I know, because my sister's is that way on her system-unchanged.



  • BDAqua Level 10 Level 10 (121,165 points)

    I think I'd turn off TM, reboot, change the icons you want, then turn on TM again & see what is what.

  • knarfrh60 Level 1 Level 1 (0 points)

    I completely shut down the whole system...iMac and the two externals.  Waiting a bit, and then brought it all back up and just for ha-ha's did Get Info and ran OmniDisk again on the 250GB and it still looks good - totally clean.  I did Get Info on the iMac and ran OmniDisk on it and they both agree on 150GB.  When I went to Time Machine it's said 200GB so I completely cleared it out of any settings...went back in and made sure the backup was correct and it now is calculating correctly-150GB. There was something in those settings that were incorrect previously. I haven't started it yet.


    Once I begin this new backup with Time Machine do I have it correct that the most will ever contain is 150GB, the capacity of the iMac?  I've never seen any backup larger than the original...but just wanted to make sure this software isn't doing something I don't understand...hopefully I will not see it creeping up to 500GB like when we started.

  • knarfrh60 Level 1 Level 1 (0 points)

    Just wanted to let yoo know that after the work that we did was complete, and Time Machine backed up correctly I went ahead and upgraded to Mountain Lion.  Once again, everything that happened before happened again.  I posted on to OS 10.8 forum:



    Everything is exactly as before. The icon, the indication the 250GB is holding a TB, etc.


    Maybe I have to delete it again and start over.

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