[amluto]

> Optane memory

Which “Optane memory”? The NVMe product always worked on non-Intel. The NVDIMM products that I played with only ever worked on a very small set of rather specialized Intel platforms. I bet AMD could have supported them about as easily as Intel, and Intel barely ever managed to support them.

[wtallis]

The consumer "Optane memory" products were a combination of NVMe and Intel's proprietary caching software, the latter of which was locked to Intel's platforms. They also did two generations of hybrid Optane+QLC drives that only worked on certain Intel platforms, because they ran a PCIe x2+x2 pair of links over a slot normally used for a single X2 or x4 link.

Yes, the pure-Optane consumer "Optane memory" products were at a hardware level just small, fast NVMe drives that could be use anywhere, but they were never marketed that way.

[myself248]

Exactly. I happen to have all AMD sitting around here, and buying my first Optane devices was a gamble, because I had no idea if they'd work. Only reason I ever did, is they got cheap at one point and I could afford the gamble.

That uncertainty couldn't have done the market any favors.

[amluto]

I feel like this is proving my point. You can’t read “Optane” and have any real idea of what you’re buying.

Also… were those weird hybrid SSDs even implemented by actual hardware, or were they part of the giant series of massive kludges in the “Rapid Storage” family where some secret sauce in the PCIe host lied to the OS about what was actually connected so an Intel driver could replace the OS’s native storage driver (NVMe, AHCI, or perhaps something worse depending on generation) to implement all the actual logic in software?

It didn’t help Intel that some major storage companies started selling very, very nice flash SSDs in the mean time.

[wtallis]

> were those weird hybrid SSDs even implemented by actual hardware, or were they part of the giant series of massive kludges

They were definitely part of the series of massive kludges. But aside from the Intel platforms they were marketed for, I never found a PCIe host that could see both of the NVMe devices on the drive. Some hosts would bring up the x2 link to the Optane half of the drive, some hosts would bring up the x2 link to the QLC half of the drive, but I couldn't find any way to get both links active even when the drive was connected downstream of a PCIe switch that definitely had hardware support for bifurcation down to x2 links. I suspect that with appropriate firmware hacking on the host side, it may have been possible to get those drives fully operational on a non-Intel host.

[amluto]

Why on Earth did Intel implement this as a 2x2 device? They could have implemented multiple functions or they could have used a PCIe switch or they could have exposed their device as an NVMe device with multiple namespaces, etc. (I won’t swear that all of these would have worked nicely. But all of them would have performed better than arbitrarily splitting the link in half.)

Maybe they didn’t own any of the IP for the conventional SSD part and couldn’t make it play ball?

[wtallis]

The Optane side of the drive used the same x2 controller as the pure-Optane cache drives. The NAND side used a Silicon Motion controller, same as their consumer QLC drives of the era. They almost literally just crammed their two existing consumer products onto one PCB and shipped it. Intel was never interested enough in the consumer applications of Optane to design a good, useful SSD controller around it, and they weren't going to let a third-party like Silicon Motion make an Optane-compatible controller.

[fc417fc802]

Or perhaps they just made a number of incredibly poor decisions. They seem to have been doing that for the better part of a couple decades now.