Compaq unveils Ultra3 storage technology

Compaq Computer`s introduction of its new industry-leading Ultra3 technology with data transfer rates of up to 160MB/second will set a new benchmark in universal storage devices.

At the same time, the technology will also offer better performance potential and unmatched investment protection for Compaq`s Ultra2 LVD customers.

Julian Simpkins, Compaq`s Storage Business Manager, said the new technology, which has been kept under wraps for the past nine months, would make a major contribution to the company`s NonStop eBusiness competency.

The new Ultra3 devices are key components of Compaq`s Enterprise Network Storage Architecture, a comprehensive approach to building the storage utility for Nonstop eBusiness.

"In the interest of protecting the infrastructure costs of existing Ultra2 LVD servers and storage solutions, customers should expect complete compatibility between existing Ultra2 products and newly available Ultra3 technology. Ultra3 should be nothing less than an extension of the existing Ultra2 LVD infrastructure," Simpkins said.

The new Ultra3 devices are key components of Compaq`s Enterprise Network Storage Architecture (ENSA), a comprehensive approach to building the storage utility for NonStop eBusiness, allowing storage to be a highly available and flexible shared resource throughout the enterprise.

Customers will be able to begin purchasing Compaq`s new Ultra3 products as they become available, and all the customer`s Ultra2 and Ultra3 products will inter- operate on the same SCSI channel, in the same server or in the same storage enclosure.

Simpkins said that while the underlying technology of Low Voltage Differential SCSI is capable of supporting "mixing and matching" of Ultra2 and Ultra3 SCSI protocols, the challenge to make it all work together required significant planning and engineering.

"Realizing that there are many possible sources of SCSI technologies, Compaq has taken great care to insure the inter-compatibility between Ultra2 and Ultra3 storage. Having control over the entire storage solution design (controllers, server back-plane, storage enclosure) and having great influence among the disk drive manufacturers, Compaq has gained a significant advantage in bringing Ultra2 and Ultra3 technology to the market in a unified solution for the customer."

Ultra3 is the latest SCSI protocol transfer speed. Like Ultra2 SCSI, Ultra3 resides on a Low Voltage Differential electrical bus and utilizes SCA drive connectors on the drive device itself. Ultra3 has doubled the total possible bandwidth for maximum data transfer again. This does not mean performance will necessarily be faster for any one application use of Ultra3, but the possibility for greater total performance is higher. The maximum total bandwidth for Ultra3 is 160 MB per second (MB/s).

"Given all the right technology architectures and applications, performance increases between Ultra2 and Ultra3 can be measured." Simpkins said.

Although it is possible to see performance gains in some benchmarks because of a new SCSI protocol (e.g., streaming video applications and large block transfers), the factors that most impact performance are:

• Underlying RAID controller processor architecture

• RAID controller firmware architecture

• OS driver development

• Hardware RAID engine design (ASIC supporting RAID 5 operations)

• The rotation speed and access times of the drives

Since every server vendor has access to faster spindle disk drives, it is important to understand what a server vendor has done to optimise the other elements of the server IO to reach the highest possible performance characteristics of the underlying storage architecture.

When Ultra2 devices and Ultra3 devices are found on the same Ultra3 SCSI bus, the Ultra2 devices will transfer data up to 80 MB/s, while the Ultra3 devices will transfer data up to 160 MB/s. If the SCSI bus is only capable of supporting Ultra2, all LVD devices will have a maximum ceiling transfer of 80 MB/s.