Yes, this is a commissioned white paper, but that doesn’t preclude my taking the same unbiased approach my clients have come to expect. Kaminario has re-thought how SSDs should be used in storage, and that deserves some attention.
It’s only six pages, but even so I will condense the content for this post: Flash is tricky Continue reading
At last week’s USENIX conference UCSD researcher Laura Grupp presented a paper that attracted a lot of attention. The paper, which had a somewhat misleading title: The Bleak Future of NAND Flash Memory predicts that NAND-based SSDs of the future: “may be too slow and unreliable to be competitive against disks of similar cost in enterprise applications.”
Today Hitachi announced the company’s second generation Ultrastar SSD400S.B family, which Hitachi claims to be the industry’s first 25nm SLC enterprise-class SSD family.
The new Hitachi SSDs support a SAS 6Gb/s dual port interface. SLC NAND flash was chosen for its high write performance and endurance.
Maximum sequential read speeds of 536MB/s and a sequential write speed of up to 520MB/s with 57K random read IOPS and 25K random write IOPS help to give ultra-fast access to data.
Intel has announced a new SSD for the Enthusiast/Gamer market. Intel’s fastest drive to date, this SSD, formerly known as “Cherryville” but now called the 520, is the first Intel SSD to use a SandForce/LSI controller and is made using Intel’s own 25nm flash.
Intel worked with SandForce for a year and a half to produce an SSD that met Intel’s rigorous standards, and made hundreds of changes to SandForce’s firmware. Users of SandForce controllers can differentiate their SSDs through the addition of features in the SSD controller’s firmware. Intel did this by tapping into its expertise in end-to-end data protection (something the company learned when working with Hitachi to introduce that company’s Intel-based enterprise SSDs) while harnessing Intel’s deep understanding of its own NAND flash and of the I/O needs of the PC.
End-to-end data protection is not a trivial feature: Continue reading
SSD endurance is an important concern that stands in the way of SSD adoption in a number of data centers. Since flash is new to the enterprise (and computing systems are a new market for flash) important issues including wear specifications still need to be hammered out.
Until flash SSDs started experiencing adoption in standard computing environments, nobody really anticipated the difficulties that would arise from flash’s inherent wear-out mechanism. Most flash manufacturers erroneously believed that Continue reading