Modern disk technology provides access to large amount of persistent data, but access times are not fast enough. DRAM offers fast access to data, but it’s generally not feasible to store one and a half terabytes of data for CPU intensive computation without involving IO.
Various NVRAM solutions have been used to address the needs for speed and capacity. NAND flash offers capacity for a resonable price, but is slow and not byte-addressable. NVDIMMs offer speed and are byte-addressable, but capacity is limited.
A new technology developed jointly by Intel and Micron, 3D XPoint, ticks all the boxes. Intel Optane DC PMEM is a product from Intel that uses 3D XPoint technology. In this blog post Jane Chu covers persistent memory (PMEM), support for it in Oracle Linux, and provides examples on how to use it.