iMac Pro FUSION drive component upgrade

[AIRaquarian]

I feel I have a pretty good understanding of the fusion drive and its components thanks to this post: https://www.reddit.com/r/mac/comments/qj0ftk What I want to know is if the fusion drive can be comprised of the PCIe SSD and a SATA SSD or doesit have to be a SATA HDD? Since the PCIe SSD should have considerably faster rates (depending on the #of channels) I would hope that it could still take advantage of the FUSION theory. ALSO,
I am tempted to increase the ram from 16 to the max but I am thinking with a 1TB PCIe SSD would I even need it? At that point wouldn't the PCIe SSD act as sort of an extension of the memory? or would it still benefit with additional ram?

 

[Bigwaff]

First, storage and memory are two completely different system components. One does not "extend" the other. Upgrading the memory is a good idea and will provide real benefits. Second, Fusion Drives are a thing of the past when HDD where large capacity storage and SSD where expensive and small capacity storage. The SSD is used as a fast cache for recently or frequently accessed data on the HHD. Fusion Drives were notorious for their unreliability and failure rates. Your iMac does not require a Fusion Drive. Install a high capacity SSD and simply enjoy faster and more reliable storage.

What I want to know is if the fusion drive can be comprised of the PCIe SSD and a SATA SSD or doesit have to be a SATA HDD?

Make a Fusion Drive out of two SSD's? Use one SSD as a fast cache for data on the other SSD? SSD's are already fast. No need for cache layering. I see little benefit to this idea, only the caveat of creating unreliable storage layer out of individually reliable storage.

 

[Fishrrman]

Hmmm....
iMac "Pro" ??
Fusion drive ??

Didn't all the iMac Pros come with SSDs installed?
(no fusion drives at all?)

I could be wrong.

 

[AIRaquarian]

Just want to provide some follow up;
I jumped through the hoops mainly to satisfy my need to know and I am glad I did. I installed a Western Digital Blue SA510 1tb SATA SSD internally and kept my APPLE PCIe 32gb SSD. I realize memory is a separate entity and felt 16gb should be plenty so it remained as is.
The results were rewarding. In the screen shots included you can see the WD SSD result independent and the PCIe 32gb SSD independent and lastly the result of the two SSD's combined as a fusion drive. You will see that the combination brought the WD SSD incredibly higher when combined as a fusion drive. Maybe it is because the data being transferred in the test never exceeded 32 gb - the capacity of the PCIe SSD, therefore it could be an illusion. Either way I can honestly say this IMac is a performer now. Not seeing hangs or pauses everything seems very responsive. If you click on the picture you will see all 3 test results.

 

[Regulus67]

Real iMac Pro speed test
To be fair. The OP did never said he has an iMac Pro. Even if it is filed under this in the forum