Fusion drive with FireCuda SSHD?

[toke lahti]

I have this set up in my mini2012.
Now the system (10.12.6) went black becaus od Security update.
I've also had some beach balls before and other hickupps, but I've thought that's because I have lots of pixels (30"+23") connected to mini.

Now I'm thinking if there might be something wrong with Fusion drive (128GB+2TB). Could it be fooled by my sshd, acting so fast with its ssd-like cache?
Is there any logs or data somewhere in the system how well it works?

And please, lets not start another talk about should FD be used at all. I just want some hard data to decide what to do. After that, I could go to plain ssd + homedir sshd, if the problem isn't solved with having FD.

 

[toke lahti]

Found few posts in reddit, that Fusion has problems sshd.
Nobody knows if there's any way to command Fusion to identify sshd "as the slower one", even if it's very fast part of the time (because of the ssd cache)?