It seems obvious in retrospect, but persistent memory adds a pretty exciting new advantage for persistent data structures.<p>Another thought: As potentially paradigm changing technology like this becomes available will it ever make sense to redesign the OS?
While there are some analytics workloads that will benefit tremendously, the main use case will be improving server utilization.<p>Currently RAM is not a compressible resource like CPU. However many applications don't have a fixed or if easily predictable RAM footprint and so you have to overprovision. Swap has been there to solve that but with its performance impact, it often can't be used for server applications.<p>These DIMMs will blur the boundary between memory and swap and make swap again viable.
One interesting thing for databases is that as nonvolatile storage latency decreases, traditional btrees get more attractive relative to newer log-structured designs. Especially if the write endurance is increased as well over current SSDs.
There's so much amazing stuff I could do with this. Imagine persistent redis? Huge huge pages? Booting from a DIM?<p>The possibilities are endless.
I guess in a theoretical NVM-only system you could pull the plug at any time, and instantly resume it when the power is back on? If I'm reading right though the latency of 3DXP is somewhere in the 10-20us ballpark, still 100-1000x slower than DRAM.
Price. Remember the current DRAM is 2.5x the price of what is was two to three years ago. So the XP DIMM being 4x cheaper then DRAM Now isn't that much different if DRAM dropped back to its median level.
On a few occasions I've found myself in the presence of a senior engineer at a large defense company who would never stop talking about how persistent memory will change everything forever. Fair enough, but he'd go on about it in the weirdest ways. I think his impression is that the CPU registers would also be nonvolatile. I'm concerned that guy might be a few electrons short of a full orbital.
The initial release was really underwhelming, given the hype around this. So my personal (uninformed) expectations is just incremental improvement to the initial product.