There will be a sea change in the non-volatile memory (NVM) market over the next five years, with more dense and reliable technologies challenging dominant NAND flash memory now used in solid-state drives (SSDs) and embedded in mobile products.
As a result, server, storage and application vendors are now working on new specifications to optimize the way their products interact with NVM, moves that could lead to the replacement of DRAM and hard drives alike for many applications, according to the Storage Networking Industry Association (SNIA) technical working group.
"This [SNIA] working group recognizes that media will change in next three to five years. In that time frame, the way we handle storage and memory will have to change," said SNIA technical working group member Jim Pappas. "Industry efforts are under way to remove the bottleneck between the processor and the storage."
Pappas, who is also the director of technology initiatives in Intel's Data Center Group, noted there are more than a dozen non-volatile memory competitors coming down the pike to challenge NAND flash. Those technologies include Memristor, ReRam, Racetrack Memory, Graphene Memory and Phase-Change Memory.
"What is happening across the industry with multiple competing technologies to NAND flash is the memory that goes into SSDs today will be replaced by something very close to the performance of system memory," Pappas said. "So now, it's the approximate speed as system memory, but yet it's also nonvolatile. So it's a big change in computing architecture."
For example, last year IBM announced a breakthrough in phase-change memory that could lead to the development of solid-state chips that can store as much data as NAND flash technology but with 100 times the performance, better data integrity and vastly longer lifespan.
SNIA's Non-Volatile Memory (NVM) Programming Technical Working Group, which includes a who's who of hardware and software vendors, is working on three specifications. First, the group wants to improve the OS speed by making it aware when a faster flash medium is available; secondly, it wants to give applications direct access to the flash through the OS; and lastly, it wants to enable new NVMs to be used as system memory.
"Most significantly, when you use non-volatile memory in the future, you can use as part of it for your memory hierarchy and not just [mass] storage," Pappas said.
Among the companies backing the specifications effort is IBM, Dell, EMC, Hewlett-Packard, NetApp, Fujitsu, QLogic, Symantec, Oracle, and VMware.
NAND flash accessed like hard drives today
Today, a processor accesses system memory (DRAM) directly in hardware through a memory controller. The memory controller is usually integrated into the microprocessor chip. There is no software necessary. It is all performed in hardware.
By contrast, a microprocessor talks to NAND flash the same way that it accesses a hard drive. It does that through operating system calls which in turn drives the traditional storage software stack. From there the OS then transports the data to or from the flash memory (or hard drive) over independent storage interfaces such as SCSI, SAS or SATA interface hardware.