Help with Disk space issue on MBP Retina 15''

[mm1250]

Hello,

So I wanted to split up my MBP Retina to install Windows via Bootcamp. I Need about 70GB partition configured so I load up Bootcamp and the most it will allow me to configure my Windows partition is 49GB. So I canceled out the install and did some checking:

According to The Get Info on my Mac HD, I have over 127GB of free space.
But if I goto "About this Mac" it only shows 57GB of free space. So i'm a bit puzzled at this. (see attached screenshot). It appears Backups takes up 69GB and Other takes up 58GB. I have no idea where these are located, I backup on an external Time Machine USB drive, so i'm unsure why they are also sitting on my Mac. Anyone have any ideas?

 

[EZMacCPA]

Local Backups and Mountain Lion

What I believe you are seeing are the local backups that Mountain Lion makes when your external drive isn't connected. In theory that space is "available for deletion if necessary" which is why Finder will often show a much larger free space than other utilities will (Finder figures it can wipe those files out).

I've not created a BootCamp partition (I just use Fusion), but as I recall one of the quirks of creating one is that Disk Utility has to be able to create what it sees as a chunk of contiguous disk space and there's only so much "clean up" it will do. I wouldn't doubt these local backups, even if deleted, may be getting in the way of what disk utility wants to do.

The size of SSDs would complicate this since the drive tends to be smaller. I'm not sure how much "smarts" are built in to handle that issue, or whether Disk Utility even considers the creation of new partition for BootCamp to be one where it's "OK" to wipe out local backups.