Intel Optane DC Persistent Memory, a year later

Last summer, we announced the Optane DC Persistent Memory blog — the Optane memory based on 3D XPoint modules in DIMM format. As it was then announced, deliveries of the Optane planks began in the second quarter of 2019, by this time they had accumulated enough information, which was so lacking then, during the announcement. So, under the cut - technical characteristics and models of using Optane DC Persistent Memory , as well as all kinds of infographics.

So, as already mentioned, Optane DC Persistent Memory modules (Optane DC PM) are installed in standard DDR4 DIMM slots, but their use requires support by the memory controller, so this type of memory can only be used with the second generation Intel Xeon Scalable Gold or Platinum processors . In total, one Optane DC PM module can be installed per memory channel, that is, up to 6 modules per socket, that is, a total of 3 TB or 24 TB per 8-socket server.


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Optane DC PM is supplied in 3 sizes: 128, 256 and 512 GB - much more than the currently available DDR DIMM strips. There are two main ways to use it and interact with traditional memory.

• Memory mode - does not require any application modifications. In this mode, Optane DC PM is used as the main addressable RAM, and the available volume of traditional DRAM is used as a cache for Optane. Memory mode allows applications to provide a significant amount of RAM at a significantly lower price, which can be important when hosting virtual machines, large databases, and so on. It should be borne in mind that in this mode, Optane DC Persistent Memory is volatile, since the data in it is encrypted with a key that is lost during a reboot.
• Direct access mode - applications and software have the ability to directly access Optane DC PM, which simplifies the call chain. Also in this mode, you can use the existing storage APIs, which allows you to work with memory as with an SSD and, in particular, load from it. The system sees Optane DC PM and DRAM as two independent memory pools. Your advantage is large in size, non-volatile, fast and reliable storage for demanding data exchange applications and system needs.

An intermediate variant is also possible: some of the Optane DC PM strips are used in memory mode, and some in direct access mode. The next slide shows the benefits of using Intel Optane DC Persistent Memory to host virtual machines.



Now we give the TTX memory modules.

And finally, about the price. The official recommended Intel prices have not yet been published, but a number of the company's trading partners have already begun to collect pre-orders, at $ 850 - 900 for the bar of 128 GB and $ 2,700 - $ 2,900 for 256 GB. 512 GB is not yet offered, apparently, they will appear later than others. Thus, the unit cost starts at $ 7 per GB, which is comparable to the price of a gigabyte of server memory RDIMM.