How do I know if the fusion drive is working?

[davefur]

Hi guys,
I had to format the MacMini (Late 2014).
Now I have installed Catalina 10.15.4, it is much slower than before and I think the fusiondrive is not working properly.
Can you tell me how to understand? thanks

 

[Fishrrman]

I believe a 2014 Mini with a fusion drive will have a 128gb SSD portion (regardless of the size of the HDD portion).

In that case, what I'd do is:
1. DE-fuse the fusion drive into "standalone" SSD and HDD drives.
2. Install Catalina onto the SSD portion, along with your apps and basic (i.e., "stripped down") account
3. Keep "large libraries" of stuff (movies, music, and pics) on the HDD portion. They don't "need the speed" of the SSD.

My prediction is if you do this, the overall performance of the Mini will "jump up" to very usable. You'll have to get used to that "second HD icon" on the desktop (easy).

Actually, if it was me, I'd be using Mojave instead of Catalina.
Which is what I'm doing with my 2018 Mini...

 

[Boyd01]

I believe a 2014 Mini with a fusion drive will have a 128gb SSD portion (regardless of the size of the HDD portion).

I split the 128gb SSD from the 1TB hard disk in my 2014 2.8ghz i5/8gb Mini with a Fusion Drive. It's running Mojave and is very fast. But this machine is just a media server and not an all-purpose computer. All my media is on a 4tb USB 3 external SSD.

FWIW, I just installed Catalina on the original Apple internal 256gb SSD on my 2012 quad Mini server. Have not really spent any time using it yet, but the install took a bit over 50gb of space. It seems to be fast, from what I've seen so far.

So I agree, split your fusion drive and install MacOS on the 128gb SSD. You can then use the hard disk as @Fishrrman describes. Or, if you want better performance, get an external SSD. The smaller ones have gotten pretty inexpensive.