Using 3D Xpoint as an intermediary memory layer between DRAM and NAND is one of the most promising aspects of Intel's and Micron's new persistent media, but the speedy new DIMM form factor retreated into the shadows after the Storage Visions 2015 conference. The disappearance fueled many of the rumors that 3D XPoint isn't living up to the initial endurance claims, largely because using the new media as memory will require much more endurance than storage devices need. Aside from Intel CEO Brian Krzanich's casual mention during the company's Q4 2016 earnings call that products were shipping, we haven't seen much new information.
That changed this week as Intel conducted the first public demo of working Optane memory DIMMs at the SAP Sapphire conference. Intel demoed the DIMMs working in SAP's HANA in-memory data analytics platform. Neither company revealed any performance data from the demo, but the reemergence of the Optane DIMMs is encouraging.
3D XPoint-powered Optane DIMMs will deliver more density and a lower price point than DDR4 solutions, which is a boon for the booming in-memory compute space, HPC, virtualization, and public clouds. Intel will ship the DIMMs in 2018 in tandem with the Cascade Lake refresh of the Intel Xeon Scalable family platform.
In the interim, Intel offers its value-add Memory Drive Technology in tandem with its new "Cold Stream" DC P4800X Optane SSDs (which we've tested). The software merges the DC P4800X into the memory subsystem so that it appears as part of a single large memory pool to the host. The software doesn't require any changes to the existing operating system or applications, but it's supported only on Intel Xeon platforms. The Memory Drive Technology is probably one of the most important aspects of the DC P4800X launch, as other methods of enhancing the addressable memory pool tend to be kludgy and require significant optimization of the entire platform at both the hardware and software level, which hinders adoption. A plug-and-play SSD solution will enjoy tremendous uptake, but moving up to the DIMM form factor addressed with memory semantics will provide even more of a benefit. The industry has been hard at work enabling the ecosystem, so servers and applications should greet the new DIMM form factor with open arms.
Amazon Web Services recently announced that it's developing new instances that offer up to 16TB of memory for SAP HANA and other in-memory workloads, and new AWS HANA clusters can pack a walloping 34TB of memory spread among 17 nodes. AWS hasn't released an official launch date for the new instances, but in light of the recent SAP HANA demonstration with Optane DIMMs and the fact that the new AWS instances aren't available yet, it's easy to speculate that Intel's finest are a factor in enabling the hefty memory allocation.