Time Machine & Space Requirements

Discussion in 'Mac Apps and Mac App Store' started by HvyMtlPlyr, Sep 17, 2010.

  1. HvyMtlPlyr macrumors member

    Jun 25, 2010
    My iMac is currently using 192GB of the 1TB drive. I currently have a 250GB drive I'm using as a backup. My Time machine backups are starting to fail as it's telling me I only have about 60GB free, but it needs 85GB to do the backup. Any idea why it needs all the extra space?

    Also, I know TM keeps several copies of the files based on the date - is there a way to purge older files (e.g. delete anything > 1 month old)?

    I'm going to eventually get a larger drive for backups, but thought I had plenty of time since I'm only at 75% capacity on the backup drive.

    Just curious. Thanks,

  2. tpg macrumors regular

    Mar 19, 2010
  3. HvyMtlPlyr thread starter macrumors member

    Jun 25, 2010
    TPG - thanks for your reply and info on the backups. I'll check it out this weekend. Long story short:

    - I had a bunch of video files that were copied form my windows machines (already on the iMac & backed up in Time machine).
    - I used handbrake to convert them to MP4's and then imported them into iMovie
    - I then deleted the original files and the MP4's
    - I know iMovie uncompresses them so a 1GB MP4 comes out to about 4GB in iMovie.
    - But still, when all was done my drive went from about 170GB to 192GB - still much less than the 250GB.

    Thanks again!

  4. HvyMtlPlyr thread starter macrumors member

    Jun 25, 2010
    Thanks Jolly. I think this may be my problem (from one of the FAQ's on the link you provided)...

    "If you do a lot of step-by-step processing of large files, such as video processing, you might want to do it on a "scratch" disk, partition, or folder that’s excluded, so the intermediate steps won't all be backed-up. When done, be sure to put the finished product somewhere it will be backed-up."

    I'll see if I can go through the backup as TPG suggested and remove those .M2TS & .MP4 files.

    Thanks again!
  5. Jolly Giant macrumors 6502a

    Jolly Giant

    Sep 15, 2010
    Hamburg, Germany
  6. gnasher729 macrumors P6


    Nov 25, 2005
    You get an error if your last backup, plus all the changes since your last backup, don't fit. So deleting old stuff won't help, if it would help then Time Machine would have done it. But it will refuse to remove the last backup until the next one is finished (in case your computer crashes while doing the backup).

    What you can do: Pick a large folder, best would be one that has lots of new stuff, go to Time Machine preferences, and exclude it from the back up (options, you may have to click on Unlock first, then add that folder in the list of folders to be excluded). Do a Time Machine backup, then remove that folder from the excluded list, and do another backup.

    After that you might consider buying a 1TB drive. I think 1 TB is about the size today where it isn't worth saving a few dollars for a smaller one.

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