Author: James Pascoe, Corporate Communications Manager,
Serial Attached SCSI (SAS) is a next-generation serial interface designed to extend the capabilities of today’s parallel SCSI drives and provide users with improved performance, system design flexibility and product reliability. SAS hard drives are expected to benefit enterprise server and storage customers who require extremely fast and reliable hard disk drives.
SAS supports data transfer rates of up to 3.0 Gb/s and full duplex, point-to-point connections so that each drive has a dedicated connection to the host. While parallel SCSI limited users to 15 drives per controller, SAS architecture supports up to 16,384 connections for much greater scalability. The enterprise interface has been designed for use in storage area networking, file sharing, workgroup and scientific/engineering environments.
Hitachi has been at the forefront of SAS development and earlier this year, began shipping the Ultrastar 15K147 – the industry’s first 15,000 RPM SAS hard drive.
The Ultrastar 15K147 is Hitachi’s highest-performer, delivering average seek times as fast as 3.3 ms, average latency of 2.0 ms and as much as 33 percent more I/Os per second than comparable 10,000 RPM products. The Ultrastar’s performance characteristics allow customers to access their data more quickly and efficiently. The drive is ideally suited for use in mission-critical enterprise computing environments, such as online transaction processing, data analysis and other multi-user applications.
The Ultrastar 15K147 is built on a mature design platform to provide greater reliability. Several Ultrastar 15K147 design attributes combine to protect customer data, including Rotational Vibration Safeguard (RVS) technology. RVS is used to protect drive performance in high rotational vibration environments, primarily in multi-drive configurations. Fluid dynamic bearing (FDB) motors deliver a low acoustic rating and improved data integrity. Hitachi also offers the only 3.5-inch enterprise-class hard drive utilizing a head load/unload ramp, which minimizes integration-induced drive damage.
The new drives are available in 36, 73 and 147 GB capacities and feature large, 16 MB cache sizes to minimize command overhead and improve average read/write response times. Hitachi’s Ultrastar 15K147 drives meet the Restriction of Hazardous Substances (RoHS) compliance directive recently issued by the European Union (EU).
For additional information about the Hitachi Ultrastar 15K147, please visit