iMac Fusion Drive clarification

Question

iMac Fusion Drive clarification

Hello All,

Happy New Year. Can someone help explain what am looking at with the screenshot of my iMac 4k Retina 2017 model? I run windows on bootcamp and needed more space. So, in that process I mistakenly formatted the "APPLE SSD SM0032L Media" drive but not sure if that is the startup disk or the SSD part of the fusion driver.

I was able to get windows running but then my Mac drive was showing a question mark, so, I used internet recovery to reinstall Monterey. However, the performance is so slow. Earlier it was so bad that I could not do anything without spinning beachball for a long time but over the past couple of days performance has improved up to the point that it is useable again. However it's still not as fast as it used to be.

So, I just want to understand what am looking at so I know what to do next. I regularly backup and luckily that has saved me when recovering both my iMac data and bootcamp windows data. So of cause before I do anything will backup again. Just trying to see how to improve the performance because I might have messed something up.

Thanks for any insight. I don't want to send it to . If that is the case then I can manage it till I upgrade.

iMac Line (2012 and Later)

Posted on Jan 3, 2022 4:02 PM

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Answer 1

Top-ranking reply

Jack-19

Level 8

46,008 points

Jan 4, 2022 12:02 AM in response to IkechukwuNwanze

You should do a backup now, not later. To start, you need an external hard drive. Here’s a few excellent ones sold by Apple:

You can then follow the steps in this Apple Support article to setup your Time Machine backup: Back up your Mac with Time Machine - Apple Support. Also, moving forward, I recommend that you use iCloud in addition to Time Machine to sync all your files and photos to all your Apple devices. Although iCloud is not a "true" backup service, iCloud can also act as an emergency off-site backup, but this is why iCloud should be used in addition to Time Machine. Here are some resources on setting up iCloud for Mac:

Jack

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Answer 2

Allan Jones

Level 9

72,092 points

Jan 3, 2022 7:36 PM in response to IkechukwuNwanze

I believe you need to start with this Apple article:

How to fix a split Fusion Drive - Apple Support

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Answer 3

Jan 8, 2022 12:07 AM in response to Jack-19

Thanks. I just did the changes and my Fusion Drive is back. The Mac part is also back to it's native blazing speed and windows running very smoothly too. This was a worthwhile exercise. Thanks both of you for confirming that was the best route to take. Recovered a huge amount of space too in the process.

Only last issue which am not bothered about is after reinstalling Monterey and windows 10 via bootcamp, a drive called: "OSXRESERVED" was created. Screenshot attached. Read up on it and it seems to be windows boot up files or something. It's about 10GB. Some say you can merge it back using Disk utility but others report that when they tried, they could not boot into windows.

Let me know what you think.

Thanks again.

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Answer 4

Jan 3, 2022 11:59 PM in response to Jack-19

Thanks both of you for the replies and links. I had gone through that when I was searching for answers. Yes, I sensed it was split into two. I have critical work to do on the machine and it's usable for now so I think I'll just continue using it as is. Once am done then will do full backup and perform the surgery as advised from the article.

Thanks again.

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Answer 5

Jan 4, 2022 12:11 AM in response to Jack-19

Thanks. I actually do a back up of my backup. So, time machine does daily backups and I have an external hard drive that I use to do a second backup. I use Western Digital and good thing I did because I could not access my time machine back up on my time capsule for some reason so this second backup helped.

I already use iCloud to sync photos, documents and also use Google Drive. Those two helped a lot when I restored. So they are like my third backup for documents, files, photos...etc while time machine and my external HDD are for my apps, settings...and getting the OS back as it was before.

Thanks of the links to the hard drives sold by . I am thinking of having an addition to my Western Digital HDD and would be good to get one sold by .

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