3D XPoint is Pretty Cool

Five years ago I wrote a post about SSDs/flash storage being a necessary ingredient for most modern build outs, and opponents were wasting time and efforts by not adopting them in their stack. While it is profoundly obvious now, at the time there was a surprising amount of resistance from many in the industry who were accustomed to their racks of spinning rust, RAID levels, and so on. People who had banked their profession on a lot of knowledge about optimizing against extremely slow storage systems (a considerable factor in the enthusiasm for NoSQL), so FUD ruled the day.

Racks of spinning rust still have a crucial role in our infrastructure, often treated as almost nearline storage (stuff you seldom touch, and when you do the performance is so out of bounds of normal expectations). But many of our online systems are worlds improved with latency in microseconds instead of milliseconds courtesy of flash. It changed the entire industry.

In a related piece I noted that “Optimizing against slow seek times is an activity that is quickly going to be a negative return activity.” This turned out to be starkly true, and many efforts that were undertaken to engineer around glacially slow magnetic and EBS IOPS ended up being worse than useless.

We’re coming upon a similar change again, and it’s something that every developer / architect should be considering because it’s about to be real in a very big way.

3D XPoint, co-developed by Micron and Intel (the Intel one has some great infographics and explanatory videos), is a close to RAM-speed, flash-density, non-volatile storage/memory technology (with significantly higher write endurance than flash, though marketing claims vary from 3x to as high as 1000x), and it’s just about to start hitting the market. Initially it’s going to be seen in very high performance, non-volatile caches atop slower storage: the 2TB TLC NVMe with 32GB of 3d xpoint non-volatile cache (better devices currently have SLC flash serving the same purpose), offering extraordinary performance, both in throughput and IOPS / latency, while still offering large capacities.

Over a slightly longer period it will be seen in DRAM-style, byte-accessible form (circumventing the overhead of even NVMe). Not as literally the main memory, which still outclasses it in pure performance, but as an engineered storage option where our databases and solutions directly and knowingly leverage it in the technology stack.

2017 will be interesting.