The mixture makes the difference

In-memory computing is a wonderful technique as long as the memory of the DB server does not collapse with the current Hana data.

Then it can also take many hours until the SAP system, SoH or S/4, gives a sign of life again. Non-volatile Intel Optane memory (Persistent Memory) should minimize the start-up difficulties!

My first R/3 installation ran on IBM RS/6000 with AIX and an Oracle database. The data was on hard disks in an external enclosure. One day the power supply to these hard disks was interrupted while the AIX server itself continued to run.

This meant that R/3 was in principle alive, but by its very nature you couldn't book! A very unpleasant situation. But after the power supply was restored, Oracle needed about a quarter of an hour for automatic reorganization and then work continued.

A Hana database server with six terabytes of main memory would take about an hour to restart in the best case scenario. With Intel Persistent Memory, IT experts at Siemens managed the restart in 1:40 minutes, as E-3 columnist "No/Name" reports in the current July/August 2019 issue on page 16.

The mixing ratio of DRAM and persistent memory was 4 to 1 in this experiment. The goal is a system configuration with equal amounts of DRAM and Optane: DRAM is naturally faster. Persistent Memory is a bit slower, but cheaper and more secure.

The data is encrypted at chip level. The task now is to find an optimum of speed, price/performance ratio and security. However, success seems certain: "No/Name" also reports from SAP's existing customer Evonik, where it was possible to improve the Hana restart phase by a factor of twelve.

Intel Optane DC non-volatile memory is a new memory technology that combines affordable high capacity and non-volatile data storage in a special way.