04/15/10
Micron using ONFI 2.1 and SATA 3.0 to leapfrog Enterprise SSDs over HDD performance
PCWorld reports that Micron will soon be rolling out Enterprise-class SSDs based on 34nm, ONFI 2.1, SLC (single-level cell) NAND Flash devices. These drives will employ the 6-Gbit/sec SATA 3.0 interface specification to create an I/O channel with enough bandwidth to support the faster Flash. Doing so makes the soon-to-be-introduced RealSSD P300 SSDs more than competitive with 10,000- and 15,000-rpm Enterprise-class HDDs, which may employ 6-Gbit/sec SATA 3.0 interfaces but cannot fully utilize the improved bandwidth because they simply cannot get the data off the read/write heads fast enough. The inherent scalable parallelism of SSD architectures makes it far easier for SSD designers to bump data bandwidth at will.
Micron will reportedly sell the P300 drives in capacities of 50, 100, and 200 Gbytes. These drives will replace the company’s current RealSSD P200 drives, which deliver sequential read speeds of up to 180 Mbytes/sec and write speeds of up to 115 Mbytes/sec while a fully saturated SATA 3.0 interface theoretically delivers a maximum bandwidth of 750 Mbytes/sec. Practical overhead issues will reduce the maximum effective bandwidth somewhat, but SATA 3.0 can clearly deliver far more throughput than currently achieved by Micron's P200 SSDs. One key to this boost is the faster ONFI 2.1 NAND Flash interface.
In contrast to short-stroked, high-rpm HDDs that require a lot of power and consequently require a lot of cooling, Enterprise-class SSDs draw far less power and require almost no cooling compared to high-rpm HDDs, so there are considerable cost considerations beyond hopelessly simplistic cost/Gbyte metrics when considering SSDs for enterprise-class storage. In addition, SSDs have predictable reliability characteristics that can help data centers avoid catastrophic storage failures in mission-critical applications such as finance and online commerce.
