Deleting old backups doesn't free up space

Discussion in 'Mac Basics and Help' started by hafr, Oct 17, 2011.

  1. hafr macrumors 68030

    Sep 21, 2011
    Using the same drive for Time Machine backups and iTunes library, I'd like to manually control the size of the backups. But I just realized that manually removing backups (either full backups or individual files) from within Time Machine doesn't seem to affect the size of the backup file.

    It's mainly the iPhoto library that disturbs me. My library is just over 40 GB right now, and having backups weighing in at 40, 35, 30 etc (you probably catch my drift) when the only version I'd ever be interested in is the most recent one just feels like an enormous waste of space.

    If I delete an old backup in Time Machine, I can no longer access it in Time Machine - but the files are still there in the backup file (the mounted Time Machine file)... How do I solve this issue without having to remove the whole backup and do a full backup from the beginning?
  2. wrldwzrd89 macrumors G5


    Jun 6, 2003
    Solon, OH
    You actually don't, because of the way Time Machine backups are structured. Unlike most backup systems, Time Machine preserves the file layout AND uses hard links to directories if the entire directory is unchanged since the last backup, to save space. This is why deleting old backups manually won't necessarily free up space. My recommendation to you, if you wish to have finer control, is to partition the drive into 2 BEFORE telling Time Machine to use it for backup - you see, Time Machine was designed to take an entire drive or partition thereof for itself.
  3. hafr thread starter macrumors 68030

    Sep 21, 2011
    I understand the concept of incremental backups and how it works ;)

    Let's say we have file F and that it weighs in at 10 GB. Now, I want to delete this file from the backup. I can choose to delete either that specific file throughout all backup images, or all backup images in which this file exists. By doing this, I have no way of restoring that file and the backup should become 10 GB lighter, right? Well, my backup remains the same size... (No, the files aren't located anywhere else in earlier or later backups.)

    Because being able to remove the possibility of restoring a file without the file actually being removed from the backup seems quite weird...

    I stopped partitioning my hard drives in the mid 90's if I intended to use both partitions at once, because of how much faster they seemed to fail than the disks I kept as single partitions, but maybe the drives are better now. I'll probably just get an additional external drive uniquely for Time Machine though.
  4. tug macrumors 6502

    Feb 3, 2010
    loughborough. u.k.
    i might be barking up the wrong tree here but where do you want to save space, on your time machine or your ext,hd.?
    to save space on your ext. just go into your ext. from finder, open backup.bdb and delete as many files as you wish.
    this will create masses of space on your ext.hd
    time machine automatically deletes the oldest backups when necessary.
  5. hafr thread starter macrumors 68030

    Sep 21, 2011
    I have Time Machine using the external hard drive for backups. It's not possible to remove files from the backup via Finder.
  6. tug macrumors 6502

    Feb 3, 2010
    loughborough. u.k.
    it is possible,
    open finder, in the sidebar you should see your ext. hd, its under devices.
    now open it.
    now amongst other things you will see a folder called backups.backupdb.
    this is where you backup history is stored.
    from here you can delete as many files as you wish, you can delete all files perhaps leaving the last weeks files only.
    now this will practically leave your ext.hd empty for you to start backing up again.
    just a note on what i posted earlier, 'time machine deletes b/ups when necessary' this only happens when using 'time capsule'. regards.:)
  7. hafr thread starter macrumors 68030

    Sep 21, 2011
    In the external drive I've got the sparsebundle. Trying to find a file there is absolutely impossible, since all files are the same size (around 8 MB). If we instead mount this and get Time Machine under devices, we find the backup database that you're talking about. Trying to delete files from here only results in a warning sign saying something in the lines of "you can't edit the backup". Ergo my earlier statement: it's not possible to remove files from the backup via Finder. At least I can't.

    Have you deleted files from the mounted sparsebundle, or are you only guessing that it's possible?
  8. mstrze macrumors 68000

    Nov 6, 2009
    Buy a larger external?

    Especially one that can also be used to back up your iTunes library. Obviously if you lose this hard drive as it is currently partitioned, you will lose the backups for your computer but not the originals (since the actual files will still exist on it) but you will entirely lose your iTunes Library as it is not currently backed up anywhere.

    2TB hard drives can be had for under $100 these days.
  9. tug macrumors 6502

    Feb 3, 2010
    loughborough. u.k.
    hi again, no I'm not guessing, i have done this myself just recently.
    perhaps my setup is different to yours, here is what I've got;

    WD 1TB ext. HD connected via usb2.

    mounted as my backup disc via time machine.

    not partitioned, perhaps that is where ours differs, i don't know.

    in finder i open it as described earlier, backupdb etc. and am able to delete any file i choose. just recently i saved around 140GB of space by doing this.

    oh, in my setup i don't get a sparse bundle, just the bdb. i think that sparse bundles are part of the time capsule setup which i also have but don't use.

    I'm sorry if i can't help you but best of luck anyway. :)
  10. hafr thread starter macrumors 68030

    Sep 21, 2011
    The problem seem to be solved. Finder is not updating the size of the .sparsebundle for some unknown reason, but it takes up less space on the disk... Strange, but I can live with it ;)

    I have an external hard drive, unpartitioned, connected to the USB port of my AEBS. Using Time Machine to back up to it.

    If I go in to my external hard drive, I have a .sparsebundle named Name's Macbook Pro.sparsebundle. If I show the contents of this package, basically the only thing you have is a folder named "bands" with loads of files all the same size.

    BUT! If you mount the backup, then in this drive (named Time Machine Backups), you have the Backups.backupdb folder. In this folder, you can see the file structure of your backup(s). But trying to delete files from here only results in the popup message "The operation can't be completed because backup items can't be modified".

    It seems very strange that you don't have a .sparsebundle and are able to delete individual files when the only difference between our setups are that you connect your drive directly to the computer and I to the router... Are you running Lion?
  11. tug macrumors 6502

    Feb 3, 2010
    loughborough. u.k.
    yes mate, i am on 10.7.2.
    however i think i can see why you can't delete the files, if you connect your ext. directly to your pro then mount it in finder, it won't create a sparse bundle, only a b/udb and then you can delete some files.
    the sparse bundle is created when using the apple base station as you are, where as i have bypassed this and connected directly to my mac.

Share This Page