Jlarimore

Thank you for the detailed explanation. I think I get it. I guess my question is, how much do parity calculations slow down the writing to my parity protected storage pool? Are they going to slow down writes from 6600MB/s to 6300MB/s or from 6600MB/s to 300MB/s. If it's the latter, I can see how I might still want to use a mover. If it's minimal, why waste a drive on it, right?

If I, knowing the risks, go ahead and make a 4 x 8tb nvme data pool, is there a reason to still use an nvme cache drive? As I understand it, the write speed bottleneck is going to come from computing/writing parity. I only have 6 m.2 slots to work with. So, the more of those that go towards storage the better. Can't RAM act as the cache?

What Tom describes is my biggest fear. These drives have the write speed capabilities to essentially self destruct if something decides to constantly write to them. I guess as long as there is a way to keep a close eye that that isn't happening I will be a little less worried.

I saw the caveat that using ssds for storage is experimental and may not work as expected. Can someone explain what might go wrong? My plan is to essentially build an itx machine with rocket 4 plus 8tb nvme drives (potentially up to 6 eventually) for storage. But, this could be a massive money pit if my plan has a fatal flaw. Is this going to work?