You should be cautious about not getting the performance you think you will get.What's there to be cautious about? I don't understand the sentence about M.2 and Optane being an oxymoron. I have 5 PCIe slots. 1 is for a 40g NIC (x8), 1 is for a GPU (x16), 1 is for an HBA (x8), and 1 holds 4 SSDs (x16).
I could use literally any drive to test this, but I'm thinking to move over 84+ TB of data just to see how large my metadata drive needs to be is a waste. And I couldn't just use any U.2 drives. I have no solution to mount them anywhere.
I was just assuming you wanted maximum performance since you're talking about Optane drives.
You have two bottle necks.
- M.2 can't to do sustained heavy workloads because of lack of heat dissipation causing it to throttle down performance.
- 4 x M.2 drives that each uses 4 PCIe lanes, mounted on a PCIe 8x card can only reach half of it's potential transfer speed.
Why not just order the NVMe drive rear option? If it's vaporware or out of stock and not manufactured anymore you wont get it.
And if you get it, your problem is solved.