Intel’s much anticipated Optane DIMMs yesterday took another step towards becoming a part of system RAM in workstations. Codenamed Apache Pass, the Optane DIMMs will be branded as Optane DC Persistent Memory. However if you feel like buying a kit for your PC you might want to hold off as the Optane DIMMs are only available in three capacities per module, 128GB, 256GB and 512GB. Plus, only the next gen Xeon processors will support them, for now anyway.
Intel’s Optane DIMMs seem to be based on their previous Optane products, leveraging the 128Gb 3D XPoint memory dies just like the Optane DC SSDs. They will be pin-compatible with the standard DDR4 DIMMs, and work in parallel with conventional DDR4 memory.
What is Persistent Memory
Persistent memory is the latest addition to the memory/storage hierarchy that bridges the gap between DRAM and storage, allowing faster and more flexible data management by placing a fast non-volatile memory between the RAM and the storage.
Persistent memory lies on the same bus as DRAM, allowing the CPU, access to data at almost the same speed and latency as conventional RAM. This lets manufacturers design systems that combine the reliability of traditional storage and the low latency and speed of DRAM.
Persistent memory is ideal for workloads consisting of large, complex data sets sensitive to downtime caused by power failures or system crashes. Applications of persistent memory include big data analytics, storage appliances, RAID cache, in-memory databases, metadata servers that store indexes and on-line transaction processing.
Intel Optane DIMMs and Apache Pass
The Optane DIMMs Intel showed off featured some fat heat spreaders, but they seem to pack 10 3D XPoint memory loads. This results in a total capacity of 640GB, but the highest capacity as per Intel is 512 GB, pointing to significantly improved error detection in comparison to conventional DRAM.
The sampling for Apache Pass has already started and will be shipped to select customers later this year. It will be made available to the broader public in 2019. Similar to how Intel did with the Optane SSD Drives, remote access will be available to developers beforehand, so they can optimize their platforms for the Optane DIMMs and Apache Pass. The developer program will run from July through August and Intel is currently taking applications for it. Developers will be required to keep their statistics secret till further given the all clear from Intel.
As of now, it is not clear whether or not it will be possible to mix and match DRAM and Optane Persistent Memory on the same memory controller channel, but the 192GB DRAM capacity for the development preview systems indicates that they are equipped with a 16GB DRAM DIMM on every memory channel. All other specifications including power consumption, clock speeds and specific endurance ratings are murky as Intel has been quite about them. This may seem ways off, but Micron has already been developing similar persistent memory solutions. Next to SSDs, persistent memory should soon become essential components of every enthusiast machine.