NV-DIMM

Where does NVRAM Fit?

AGIGARAM DDR4 NVDIMM (Photo Courtesy of AgigA Tech)There’s been a lot of interest in NVRAM recently.  This technology has been lurking in the background for decades, and suddenly has become very popular.

What is NVRAM?  Quite simply, it’s DRAM or SRAM that has a back-up flash memory a small controller, and a battery or super-capacitor.  During operation the DRAM or SRAM is used in a system the same way that any DRAM or SRAM would be used.  When power is interrupted the controller moves all of the data from the DRAM or SRAM to the flash using the backup power from the battery or super-capacitor.  When power is restored, the controller moves the contents of the flash back into the SRAM or DRAM and the processor can resume operation where it left off.

In some ways it’s storage and in some ways it’s memory, so Continue reading

White Paper: Using Flash as Memory

DRAM, Flash, and HDD HierarchyToday NAND flash is being shoehorned into HDD formats simply because it is persistent – the data doesn’t disappear when the lights go out.  This approach fails to take advantage of NAND’s greatest strength – its low cost relative to DRAM – and this prevents it from fully meeting the needs of most data centers.

Since 2004 NAND has been cheaper than DRAM, and today its price per gigabyte is an order of magnitude lower than that of DRAM.  NAND is cheaper and slower than DRAM, and HDD is cheaper and slower than NAND.

A role better suited to NAND flash technology is Continue reading

Viking: Why Wait for Nonvolatile DRAM?

Viking NV-DIMM and Supermicro serverViking Technology on Wednesday announced that the company has arranged with SuperMicro to deliver solutions that should solve issues key to flash storage array designers.  Supermicro will ship server boards that have all the hooks necessary to support Viking’s nonvolatile DDR3 DIMMs without users having to wait for this kind of support to arrive in servers based on the standard Intel platform.

Viking’s marketing folks tell me that NV-DIMM support is something that its customers have been asking for, and that it will be a standard component of Continue reading