Dot Hill Assigned 98th Patent

Dot Hill Systems Corp. announced a patented technology that improves storage performance in SAS environments.

The invention described in Dot Hill’s 98th US patent, numbered 8,812,913, “method and apparatus for isolating storage devices to facilitate reliable communication,” developed by Phillip Raymond Colline, Irvine, CA, for a method to restore communications to a SAS link if a storage device malfunctions and causes configuration changes.

The abstract of the patent published by the U.S. Patent and Trademark Office states: “A method for maintaining reliable communication on a link between an expander and a storage device is provided. The method includes detecting, by a processor coupled to the link, an error corresponding to the link, and maintaining a count of detected errors for the link, by the processor. The method also includes determining, by the processor, if the count of detected errors is above a first error threshold. If the count of detected errors is not above the first error threshold, then the method repeats the detecting, maintaining, and determining steps. If the count of detected errors is above the first error threshold, then the method provides the processor placing the storage device into a segregated zone.”

Configuration changes initiate time-consuming device discovery processes, which delay normal I/O traffic. The innovation addresses this issue by segregating a misbehaving storage device into a special domain, preventing further configuration changes and normalizing I/O traffic among all interconnected SAS links.

Benefits of the Dot Hill innovation include:

• Autonomous restoration of storage devices to operational status, with minimal need for user intervention or disruption to the overall system.
• Ability to preserve proven configurations by isolating unproven or unqualified storage devices when they are added to a storage system.
• Ability to override the separation mechanism and integrate unqualified storage devices, such as may be required in an emergency or disaster situation.
• Flexibility to dynamically manage any size pool of segregated storage devices. Storage devices may be added to or removed from the pool at any time, depending on testing status and override conditions.
• Hierarchical management of drives in storage systems.

“As we close in on our 100th patent, this latest innovation provides system administrators with more control and enhances Dot Hill’s hallmark 99.999% data availability with enhanced system robustness,” said Ken Day, CTO, Dot Hill. “Dot Hill’s vast portfolio of internally developed intellectual property allows us to deliver truly differentiated products to the marketplace that make a positive impact for our channel partners, IT professionals and the vertical markets that we serve.”