Time Machine: Fills up my backup drive too fast.
If your external hard drive is at least twice as large as the amount of data you are backing up, you should be able to get through at least a month of backups. If you can’t, there are a few very specific types of files that may be causing your problems and need to be excluded. You can exclude items from future backups to save space. Open Time Machine preferences and click Options. Then click the plus sign (+) to add items that you don’t want backed up. Make sure you have separate backups of anything you exclude.
An incremental backup works by storing all the files you’ve added or deleted since the last backup. This works well with sets of individual files because each file is stored separately. This works very poorly with applications, like Entourage, that use one large database file to store all your information. With an application such as Entourage, every time you receive an email, it changes the database file. (This was fixed in the 2011 version of Outlook for Mac.) Time Machine treats the changed database as a new file and backs up the entire database file. If you have a large email database, this can fill up your backup drive pretty fast. You can exclude database files but make sure to setup another backup plan for any files you exclude.
If you run Windows with Parallels or VMWare, your computer stores a large disk image of the entire operating system installation. This file changes every time you do anything in Windows and will fill up your Time Machine drive fast. You’ll want to exclude the disk image from Time Machine backups and use Parallels or VMWare’s snapshot feature to backup your Windows installations instead. If you use Parallels, exclude the file ending in .hdd from Macintosh HD/users/yourname/Documents/Parallels/virtual machine name. If you use VMWare, exclude the file ending in .vmwarevm from Macintosh HD/users/yourname/Documents/Virtual Machines.
If you edit a lot of large files (1GB+), you can end up filling up a backup drive pretty quickly. This is because every time you edit a large file, Time Machine will save the new version as a separate file. You may want to exclude some files or use a different backup solution.
Published March 24, 2009 12:00 PM
Last modified on November 30, 2010 2:51 PM
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