The problem is optane wasn't as fast as DRAM, nor as cheap as disk. So you still needed the conceptual split anyway, and there wasn't a compelling reason to really use it (OK, I can get a lot of RAM but it's 1/10th the speed of my normal RAM, which will kill both memory latency and memory bandwidth limited applications, which is basically any workload which wants lots of RAM. Or I can get super fast persistent storage with high durability but much higher cost, which basically makes it good for a persistent cache but not that much else, considering SSDs are now similarly fast even though their durability is not as good). It wasn't sunk by a stuck-in-the-mud way of thinking about memory versus disk, it was sunk because the tech never got good enough to actually achieve their ambitions.
Where Optane could've been used: distributed storage. The whole game there is about how fast can you ack the writes while writing as far away as you can. The company I worked for in this specific area had used pmem when that was available for that specific reason.
I'm no expert on costs of these things and especially wouldn't dare to predict how these costs could've behaved in the future, but my guess would be not that the technology had no use, rather that it was too expensive for what it was good at, and the second best was cheap enough to warrant choosing it over Optane.
Hmm, ive seen report by fujitsu that it was fine if used with dram
>Intel Optane persistent memory is blurring the line between DRAM and persistent storage for in-memory computing. Unlike DRAM, Intel Optane
persistent memory retains its data if power to the server is lost or the server reboots, but it still provides *near-DRAM performance*. In SAP HANA
operation this results in tangible benefits
>Speeds up shutdowns, starts and restarts many times over – significantly reduce system downtime and lower operational costs
Process more data in real-time with increased memory capacity
Lower total cost of ownership by transforming the data storage hierarchy
Improve business continuity with persistent memory and fast data loads at startup
