Will NVRAM replace SSDs or DRAM?
I attended a @Hewlett-Packard Enterprise ( #HPE) event in California a couple of weeks ago. @EduardoDuarte, a Senior Product Manager for media in HPE’s 3PAR group, gave an excellent talk on the role he expects storage class memory to take in systems. STORAGE CLASS MEMORY Storage Class Memory ( #SCM ) is a concept that has been talked about for years, and for good reason: it will radically change how we architect systems. It has two essential features: 1) contents are persistent (non-volatile), like storage; and, it is byte addressable, like memory. Since it has the characteristics of both, which market will it invade? A first approximation analysis: it replaces the costlier technology, i.e. DRAM. BONES Mr. Duarte began by postulating that each revolution in storage has been driven by new media. Disks wiped out a slew of media – magneto-resistive delay lines, magnetic drums, primary tape – in the then tiny computer market. 3.5″ disks killed 5.25″ disks. Thumb drives killed floppies, QIC, Zip drives, and others. SSDs have destroyed 15k disks and, soon, 10k disks. As he looked into the future the big change is the arrival of low-cost TLC (tri-level or 8 bit) and, later, QLC (quad-level or 16 bit) flash memory. TLC will be the mainstream flash technology in 2020, with QLC winning by 2025. QLC’s superpower? It’s cheaper than MLC flash – which is good, because almost every other spec is worse. In Eduardo’s opinion, 3D XPoint will find its niche as a DRAM replacement. Intel will ensure it is cheaper, and engineering will ensure reasonable performance.