Recently I'm seeing my time machine backups get big. On a typical daily time machine backup, they've gone from a gig, to 5 gigs, to today... Time machine wants to back up 329gb. I've not moved huge files around. I've not fired up VMs.

So far it's backed up 17gb of 329gb. What's going on? I'm running 10.9 on a 500gb SSD


Time machine has somehow lost the connection with the previous backups. If you have renamed your drive or large folders it can happen. If you have changed the drive it will definitely happen.

Simplest solution is to reformat the backup drive and start fresh.

  • I've made no changes to the backup drive or any big changes to my laptop's drive. My laptop has 400 GB on it. So a new full backup wouldn't fit in 320 GB. But blowing it up and starting over seems the only solution – Sparky1 Mar 12 '15 at 15:45

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