SAP HANA with Intel Optane Persistent Memory (PMEM)

SAP HANA now has a non-volatile in-memory option on Bare Metal servers. Intel Optane™ persistent memory (PMEM) retains its contents like traditional storage options but with speeds similar to main memory.

{: caption="Figure 1. SAP HANA Intel Optane PMem^[1] overview" caption-side="bottom"}

Many systems with large data storage and retrieval needs use DRAM for fast data retrieval. DRAM is costly and data does not persist when the server is rebooted or shutdown. On startup, data must be reloaded from storage.

With Intel Optane PMEM, data is retained in memory during system restarts and power outages, providing faster start times. PMEM provides near-DRAM performance and is also byte-addressable.

Intel Optane PMEM modules are installed with DRAM in the same dual in-line memory module (DIMM) slot. PMEM modules do not function without any DRAM DIMMS installed. The current configurations supports DRAM to PMEM ratios of 1:1, 1:2, and 1:4.

SAP HANA uses App Direct mode, in which the application stores data on the persistent memory. HANA2 SP04 release or higher was co-engineered by SAP and Intel to use the unique dual memory and storage capability of the PMem modules.

In App Direct mode, the applications directly access the memory and control the direct load and store of the PMem and DRAM DIMMs memory resources. In this mode, the PMem acts as byte-addressed persistent memory that is mapped to the system physical address space. App Dir mode uses regions, which are groups of one or more PMem modules that appear to be a single logical virtual address space. Regions are partitioned into one or more namespaces, similar to hard disk partitions.