If you are reading this article, it’s likely because your Macbook Air or other Apple Mac laptop has started freezing up on you, or has slowed to a crawl and is grinding away, or you may even seem to be out of disk space. If any of these are your issue, a good place to start checking is with your Mac’s ‘mobile backups’, which, despite the name, aren’t backups for your mobile devices onto your Mac, but rather are backups that your portable computer (i.e. laptop) makes to itself when you are away from your Time Capsule or other backup drive.
Yes, you read that right: your Macbook is backing itself up to itself.
Now, in theory this shouldn’t really cause any of the aforementioned issues – particularly negatively impacting disk space, because Mobile Backups is designed to leave you with at least 20% of your available disk space free. What this means is that it will keep creating new backups until you are down to 20% disk space free, then it will begin deleting the oldest backups as it creates new ones, so that you are always left with 20% of your disk space free.
But in practice, that doesn’t seem to stop it from causing slowdowns, or freezes, or from causing your computer to grind away.
We actually wrote about this about a year and a half ago, in the article All about Apple’s Mac MobileBackups and How to Disable It, but as there has been a new version of OS X since then, not to mention multiple updates, we thought it was worth revisiting.
It is neither obvious how to stop these unconnected backups, nor how to delete the ones that are already on your machine’s hard drive, so here is what you need to do:
You will need to be comfortable with command-line commands within your terminal window (so if that isn’t you, please stop here, and have someone who is familiar with this do it for you).
At your shell prompt type:
sudo tmutil disablelocal (return)
You will be prompted for your system password. Enter it and hit return, and ..that’s it! You’re done!
“But wait,” you ask, “how do I delete all the existing mobile backups?”
You don’t have to – the very act of disabling the local mobile backups also will cause them to be deleted within short order.
If you decide at some point that you want to re-enable the mobile backups, just open your terminal window, and type:
sudo tmutil enablelocal (return)
Of course, you do all of this at your own risk, but frankly the only times we have ever wanted a backup is when there has been a disk failure, so that having backups on the disk wasn’t much help (but we always make sure to make backups to our Time Capsule – i.e. a remote disk).