Should you upgrade your Fusion Drive iMac to macOS High Sierra?

“Someday far in the future, Apple will have settled fully into using its new macOS filesystem, APFS, and Macworld readers will stop being nervous and confused about it,” Glenn Fleishman writes for Macworld. “Until then, I continue to receive queries in our inbox.”

“APFS is a robust, more efficient, and futureproofed filesystem that has a lot of advantages,” Fleishman writes. “But the transition isn’t complete by any means.”

“Reader Bill emailed wondering about the safety of upgrading his iMacs to macOS High Sierra, since each has a Fusion Drive, Apple’s hybrid of SSD and hard drive,” Fleishman writes. “It’s not unsafe to upgrade, because High Sierra leaves Fusion Drives in HFS+ format. However, I’m assuming that Apple will release an update to High Sierra at some point that sweeps in Fusion Drives… [but] that could be problematic…”

Read more in the full article here.

MacDailyNews Take: Yes, we’d leave it alone until we know APFS works on every drive and with every feature.

macOS update paranoia and when will Apple’s APFS finally work on Fusion drives? – January 25, 2018
Craig Federighi confirms Apple File System coming to Fusion Drives in future macOS High Sierra update – September 26, 2017


  1. If Steve Jobs were still around we’d know that APFS works on every drive and with every feature. He’d have made sure of it BEFORE it was released. Am I the only one sick and tired of being Apple’s non-paid beta tester?

  2. It would be good to know a rough time on when to upgrade safely, however, we can’t expect that. And I’d rather not have a date until it was truly ready to go, post-beta testing and the bugs are ironed out. As my machine is a work machine, I’m not taking that risk. A return to ‘it just works’ would be a step forward. I’m patient enough to wait.

  3. APFS Is yet another instance of a bad release. And Apple is not expressing any embarrassment over this error. No one is getting canned. Apple needs to bring APFS back into its labs for further testing and refinement and then release it for real so that it can repair its reputation and we can have confidence in Apple’s future.

  4. I am about 3 weeks into High Sierra on an iMac with a fusion drive. It’s been rough, 3 attempts at an “upgrade” Once completed, a long long list of weird things happening, on restarts, various system windows opening, normal windows appearing in odd places.

    I am a daily user of about 12 3rd party apps for web animation and general graphic image work. Most of the apps have had odd things happen, very hard to even describe, I don’t have time to list them, just save, quit, restart app or iMac.

    You always see things like that in apps whenever there is an “update” but in 30 years on Mac, there has never been the number of occurrences like there is this time.

    The only apps I use are Safari, Mail, Textedit, iWork 09 occasionally,Calendar because I am familiar with it . As much as I try to prevent it, iTunes worms its way in occasionally. Nothing else of any real value or usefulness in the other Apple apps. Those are for the entertainment consumer, not the world I am in, although I produce content for it.

    Although 95% of the problems have gone away for reasons which I do not know, but knowing what I know now, I would have held at Mavericks, my work flow was more efficient. There has been a downward trend in my work efficiency with every “upgrade” but I guess I am supposed to ignore that because it’s “progress”

    1. I installed High Sierra on my iMac and my MacBook Pro about a week after release. I also did the conversion of my internal drive on my iMac to APFS, but not Time Machine. I use a lot of 3rd party apps. They have all performed in exactly the same manner as before the upgrade. Really no problems as all. Perhaps MDN should take a poll of folks who have upgraded their Macs with Fusion drives to get some idea of how common problems are.

    2. This morning had two restarts all on their own, ran Etrecheck, they list that as an issue in their popdown menu of things they have seen before. The same thing happened a couple of weeks ago.

      Haven’t had anything like that happen since I started as a Mac user in 1988.

Reader Feedback

This site uses Akismet to reduce spam. Learn how your comment data is processed.