1 Topic by Q-collective

  • Q-collective
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Topic: iMac 2012 Fusion Drive support

Hey all,

So, I'm considering an iMac 27" of the latest 2012 model, with a 3TB fusion drive. I want to install Gentoo Linux besides OS X, but according to this document Apple's Disk Utility only supports one extra partition on the normal HDD...

Can I add a partition to the hard disk with Fusion Drive?
Using Disk Utility, you can add one partition to the hard disk on Fusion Drive. Once you add the partition, the "plus" symbol in Disk Utility to add additional partitions will be grayed out. You cannot partition the Flash storage.

If I create a hard disk partition is it part of Fusion Drive?
The additional partition is not part of Fusion Drive. The new partition is a separate volume that is physically located on the hard disk drive.

So, can I just plugin the GParted USB stick, boot up in the GParted live distro and circumvent that silly block?

2 Reply by gedakc

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Re: iMac 2012 Fusion Drive support

That is a good question.  The short answer is I don't know.

My guess would be that Fusion Drive software somehow makes both a Flash drive and a hard drive appear as one drive to Mac OS X, and places the most frequently accessed files on the Flash drive to increase performance.

I would assume that Fusion Drive continues to use the Mac OS X hybrid partition table (GPT + MBR) scheme on the physical devices.  However, perhaps the Fusion Drive software cannot handle more than one extra partition on the hard drive.

To know for sure if GParted Live will work with Fusion Drive requires someone with this set up to try.

Has anyone with a Mac and Fusion Drive tried using GParted Live?

3 Reply by class413

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Re: iMac 2012 Fusion Drive support

Two web pages related to the Fusion drive:
http://www.pcmag.com/article2/0,2817,2412726,00.asp
http://arstechnica.com/apple/2012/10/mo … -your-own/

I had in mind some "caching" hard drives, that use some internal Flash storage as cache. It seems that it isn't that a fusion drive.
In addition, it seems that there is very few info available on the Fusion drive internals.

*** It is highly recommended to backup any important files before doing resize/move operations. ***

4 Reply by Q-collective

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Re: iMac 2012 Fusion Drive support

Ok, I guess I'll create a usb drive and test this on a machine I can borrow somewhere next week.

Thanks for the answers so far!