Mojave and Fusion Drives

(Alan Forkosh) #1

I’ve upgraded to Mojave on my 2018 MacBookPro with no significant issues. However, I also own a 2015 iMac with a 3TB Fusion Drive with over 2TB of data.

I understand that Mojave will convert the Fusion)?rive to APFS. Has anyone on this list already upgraded in a similar circumstance (or seen reports of others doing it?). I’m interested in any problems encountered and also in getting a rough idea of how long the conversion of the ‘drive’ will take.

Thanks in advance for any information.

(Al Varnell) #2

No personal experience, but I’ve yet to hear from anybody who did so having an issue.

It’s difficult to judge how long it takes to do the conversion since it takes place as part of the installation process, but when I did it using an SSD it appeared to be a matter of less than a minute.


(Corlin) #3

My experience: With a Mac Mini (2014) Fusion drive.
When I updated to Mojave, it automaticly converted my built in drive to APFS.
But the external spinning drives did not.
You can use Disk Utility to convert external drives to APFS.
All this was seamless and fast.

(Alan Forkosh) #4

To perhaps close out this thread:

I took the plunge and upgraded the iMac to Mojave this evening (after creating 2 external clone backups) and running Disk Utility to check for drive issues. I deliberately had no external devices (except for keyboard and pointing devices connected. Anyway, the upgrade took less than 2 hours and all appears well with the Fusion Drive converted to APFS.

(Adam Engst) #5

I’m hearing that Mojave has trouble with Macs where the Fusion drive was replaced with an SSD.

(@lbutlr) #6

I have a 2012 iMac that shipped with a Fusion drive (3TB). I replaced the SSD with a 1TB SSD which Is my boot drive and I use the 3TB rust drive for large sets of data.

No problems for me with Mojave other than my machine is 6 years old.