This article is more than 1 year old
Netlist NVDIMMS shine bright in SuperMicro's flashy boxen
Adding DRAM persistence enables safe cache writes
Applications will run faster when SuperMicro servers are fitted with Netlist NV4 non-volatile DIMMs, the firm says.
The two suppliers showed a speed increase with NoSQL Key-Value store application data stored in these NVDIMMs, thus avoiding disk, SSD or PCIe flashcard data accesses. In fact the NVDIM system was 200 percent faster with NVDIMMs than with PCIe flash card data access.
The rationale is that when data is written to a memory cache by an application it is not secure until it has been moved to persistent storage on a PCIe flash card, SSD or disk drive. The write operation to flash or disk takes time and slows down the application.
By backing up DRAM with persistent flash on the memory carrier, app speed is enhanced.
The NV4 product is an NVvault DDR4 dual in-line memory module (DIMM) with an FPGA, DRAM and flash on the card. It can store either 8 or 16GB and uses a supercapacitor for power failure protection. Netlist calls it a persistent DIMM.
The flash is there as a backup for the DRAM if power fails. The supercapacitor provides enough power for DIMM DRAM data to be written to the DIMM flash. The flash does not function as storage in the application’s memory space, instead providing persistence for cached data in DRAM.
Flash data gets written back to DRAM when power returns.
Netlist NV4 non-volatile DIMM
Samsung has invested in Netlist so as to see its NVDIMM technology in forthcoming products.
Netlist says: “'Hot' data (cache, metadata, indexes, etc.) is available at nanosecond DRAM speeds while less frequently accessed data can be stored in lower tier PCIe Solid State Drives (SSD), SATA/SAS SSDs and hard drives. In addition to dramatically improved system performance, total cost of ownership (TCO) is reduced. Instead of constantly wearing down SSDs with write cycles, data is written to the DRAM portion of the NVDIMM thus extending the life of all SSDs.” ®