Has anyone tried setting up a Fusion Drive on the ARM-based Macs? I did this many years ago on my Intel Mac Pro, and considering doing it on my M2 based Mac Mini.
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Fusion Drive on ARM Based Macs
- Thread starter melvinlusk
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The fusion drive used to be a useful method to get more storage space (and a bit more performance) at a cost-saving.
But, now that SSDs have come down in price, it no longer makes economic sense to add a spinning hard drive to the SSD that you would already have. Note that Apple no longer offers spinning hard drives (or fusion drives) in any system.
Technology moves on.
A fusion drive would be a step down from the SSD that you already have in your ARM based Mac.
But, now that SSDs have come down in price, it no longer makes economic sense to add a spinning hard drive to the SSD that you would already have. Note that Apple no longer offers spinning hard drives (or fusion drives) in any system.
Technology moves on.
A fusion drive would be a step down from the SSD that you already have in your ARM based Mac.
I am fairly confident it could not work for the boot partition. The boot drive contains volumes required to boot and verify the system before it would look for the external disk.
It might be possible to create a second partition on the internal disk and create a Fusion Drive with that and an external HDD. This would then be mounted after your login. Even if possible, I think this would be a retrograde step. Better to get a low cost USB SSD (or more expensive Thunderbolt SSD) to store files which don't fit on the internal. Of course, better still (for performance) to get a larger internal SSD!
I am much more confident that you can build a Fusion Drive with an external SSD and an external HDD. Try it!
It might be possible to create a second partition on the internal disk and create a Fusion Drive with that and an external HDD. This would then be mounted after your login. Even if possible, I think this would be a retrograde step. Better to get a low cost USB SSD (or more expensive Thunderbolt SSD) to store files which don't fit on the internal. Of course, better still (for performance) to get a larger internal SSD!
I am much more confident that you can build a Fusion Drive with an external SSD and an external HDD. Try it!
I'm not interested in using a traditional HDD. My Mac Mini has 256GB internally, and I was thinking about getting a Thunderbolt external NVMe drive to try to increase my OS and Application partition. I could always just extend the OS partition across both drives, but I'm not sure if the Thunderbolt drive will run at the same speed as the internal drive (which can't be upgraded). I was thinking that doing the traditional Fusion Drive setup would handle moving the regularly used files to the internal storage for me.
You may be able to prove me wrong, but I seriously doubt you could extend the boot/system partition across two drives.
Since you are stuck with 256GB (clearly you should have got more), leave apps, system and your user home folder on the internal disk and move all files, etc. to the external. You can use symlinks or aliases to make its use fairly seamless.
Even with the best external TB drive it will be slower - but you are unlikely to notice that. Even if you ignore all protocol overheads TB is limited to 40 Gb/s, which lower than the bandwidth of the internal.
There is a considerable overhead with shuffling files to and from the external. This is worth the overhead when the external is a HDD. It would make the whole thing slower than getting a good (expensive) external Thunderbolt SSD.
Fusion Disks are a yesterday's technology purely to make HDDs seem faster. Don't even consider them.
What is your use case and workflow? Fast disks (internal or external) are expensive.
Unless your use is in the professional video area, it is hard to justify a large fast external SSD. If your use is like that, sell the Mini and get Mini or Studio with enough internal SSD for active projects along with external SSDs for backup and long term storage.
I pity the fool who uses an external bus-powered drive as a component of a Fusion Drive. Seriously asking for data loss.
Basically, this:
Also… Apple has instructions on how to move your media libraries:
Change where your music files are stored on Mac
On your Mac, change where your Music files are stored on your computer. You can also manage your files and create folders for better organization.
support.apple.com
Move your Photos library to save space on your Mac - Apple Support
To save storage space on your Mac, you can move your Photos library to a different storage device.
Change where photos and videos are stored on Mac
In Photos on your Mac, store photos and videos in a photo library or outside of it. Copy external files into a library.
support.apple.com
Change Files settings in the Apple TV app on Mac
In the Apple TV app on Mac, set options for folder locations, automatic delete options, and more.
support.apple.com
Move your iMovie for Mac library - Apple Support
To save space on your Mac, you can move your iMovie library to an external storage device.
All ideas involving extending the size of your internal SSD with external storage won't work. Apple Silicon Mac firmware can't read anything but the internal SSD, so there are hoops to jump through if trying to boot from anything else. Apple has implemented a path to boot from a volume completely external to the Mac, but this involves copying a bunch of key system files from that external drive to a hidden volume stored on the internal SSD of the Apple Silicon Mac, and here I'm willing to bet that they haven't bothered to make Fusion Drive a valid target.
Instead of trying to come up with some janky way to merge the external thunderbolt with the internal SSD, I would just use the external drive as additional storage. Unlike some operating systems, macOS doesn't care where third party apps are located, and if written to Apple's guidelines, those apps don't care either, so there's nothing stopping you from just putting some of your apps and/or data on the external.
Are you seriously planning to boot from an hybrid made out of an internal and external drive?
I couldn't think of any better way to turn your system into a ticking time bomb.
All of you make excellent points. This is more of a thought experiment than anything. I'm using one of these for my media libraries (music, photos, etc).
eshop.macsales.com
I also use one for my Time Machine backups.
My Mac Mini isn't really all that short on space, I still have around 40 GB free with all of my usual apps installed. I can always free up more space if I need, I was just considering the options in case I get to a point where that's not feasible.
Thanks for everyone's insight.
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I also use one for my Time Machine backups.
My Mac Mini isn't really all that short on space, I still have around 40 GB free with all of my usual apps installed. I can always free up more space if I need, I was just considering the options in case I get to a point where that's not feasible.
Thanks for everyone's insight.
Pretty sure that, given how much is tied to the internal SSD (unlike any PC and any Intel or PowerPC based Mac, you have no functioning firmware on an Apple Silicon Mac without it), doing a Fusion drive would probably not work. Incidentally, so long as your applications fit on the internal drive, you can always have your data on external drives.
If one part of a Fusion drive is missing, you've got nothing. The drive will just show up as a non-working volume. So if the bootloader can't read the external drive at the EXACT same time as the internal one, before the OS itself is loaded, the whole volume breaks and you've got no OS.
Just use a 'normal' external drive, and move Photos, Music, TV libraries to that. Make sure you've got another drive that is backing up both your internal and external drives, though.
Just use a 'normal' external drive, and move Photos, Music, TV libraries to that. Make sure you've got another drive that is backing up both your internal and external drives, though.
You can completely use a external drive as Systemdrive. I also use an external WD850X in a Acasis Thunderbolt case as my Systemdrive on a Mac Studio.
Speed is around 3000 MB/s and work without any problems. If I’m right, the 256 MB model only work with 1500 MB/s. So the external drive is twice as fast.
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