New SSD Introductions from Seagate and Micron
December has been a big month for new entrants in the SSD (solid-state disk) market. Two big-brand contenders that announced products this month are Seagate and Micron. SSDs represent new product lines for both of these companies. Seagate Technologies, started initially as Shugart Technologies by the godfather of storage Alan Shugart, essentially launched the small hard-disk drive (HDD) revolution in 1980 with the 5.25-inch ST506, which had a whopping storage capacity of 5 Mbytes. Micron is a leading semiconductor memory vendor and its NAND Flash chips are going straight into its SSDs.
Seagate announced its Pulsar SSD line on December 7 or 8 (depending on which version of the press release Google finds for you), allowing a show to drop that people had expected for more than a year. Pulsar drives use the familiar 2.5-inch HDD form factor and a SATA interface, making it easy to drop the drives into existing computer and server systems. Seagate’s Pulsar SSDs employ SLC (single-level cell) NAND Flash devices, which cost more per bit than MLC (multi-level cell) and TLC (three-level cell) NAND Flash devices. In exchange for the higher cost, you get more reliable memory, as was discussed in this blog a while back. (Check out “More than Moore: SLC, MLC, and TLC NAND Flash.”)
Seagate Pulsar SSD
The use of SLC NAND Flash underscores Seagate’s focus on enterprise-class storage for the SSD. There are at least two good reasons for Seagate’s enterprise focus. First, enterprise customers are more able to translate an SSD’s speed advantage over HDDs into dollars (as previously discussed in the blog entry “SSD TCO (Total Cost of Ownership”). Second, SSDs are a premium product with a premium price. Enterprise customers more easily accept the higher cost/Gbyte price tag attached to SSDs. Seagate’s Pulsar SSDs are available in storage capacities to 200 Gbytes and the SSDs achieve “a peak performance of up to 30,000 read IOPS and 25,000 write IOPS, 240MB/s sequential read and 200 MB/s sequential write” according to Seagate’s press release. The Pulsar drives have a 5-year limited warranty.
Micron Technology rolled out its RealSSD C300 less than a week before Seagate’s SSD announcement. The first glaringly obvious difference in Micron’s C300 SSD is that it sports a 6-Gbyte/sec SATA 6.0 interface. However, the faster interface alone will not boost performance (discussed earlier in this blog here) if the drive internals aren’t designed to sustain high transfer rates supported by SATA 6.0. To that end, Micron’s RealSSD C300 press release discloses the fact that the new Micron SSD “leverages a finely tuned architecture and high-speed ONFI 2.1 NAND Flash to provide a whole new level of performance.” (ONFi, the Open NAND Flash interface, is discussed in this previous blog entry.) The result: a read throughput speed of up to 355MB/s and a write throughput speed of up to 215MB/s.
Compare those numbers to Seagate’s Pulsar and you’ll see that the Micron drive’s read throughput is nearly 50% faster but the write throughput is only 7.5% faster. Write throughput is one of the Achilles’ heels of SSDs. NAND Flash devices had an erase/write cycle that simply takes time.
Micron RealSSD C300
Micron’s C300 SSDs will be offered in 1.8-inch and 2.5-inch form factors, with both form factors supporting 128- and 256-Gbyte capacities. Micron is currently sampling the C300 SSD in limited quantities and expects to enter production in the first quarter of calendar 2010.
Both companies are making smart moves into the SSD market. Seagate, like Western Digital and its acquisition of SSD vendor SiliconSystems in March of this year, recognizes that it’s not in the HDD business—it’s in the storage business and SSD storage is hot right now. Micron, like Intel, sees SSDs as a value-added way to package and market it’s NAND Flash devices. Both companies have made very smart moves into the SSD market.