The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 22, 1997
Filed:
Feb. 01, 1995
Theresa A Burkes, Meridian, ID (US);
Bryan M Diamond, Boise, ID (US);
Marvin D Nelson, Boise, ID (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A hierarchic disk array data storage system has a disk array with multiple storage disks and a disk array controller which coordinates data transfer to and from the disks. The storage disks define a physical storage space. A RAID management system maps a RAID-level virtual storage space onto the physical storage space. The RAID-level virtual storage space presents the physical storage space as multiple RAID areas. The RAID areas include mirror RAID areas which contain mirror allocation blocks to store data according to mirror redundancy and parity RAID areas which contain parity allocation blocks to store data according to parity redundancy. The RAID management system dynamically migrates data between the mirror and parity RAID areas in a manner which optimizes performance and data reliability. As new storage requests are made, the RAID management system evaluates the existing storage conditions and computes a total virtual capacity that is available to the user given a disk array configuration. A total virtual capacity can be calculated without including the capacity of any given storage disk in the disk array data storage system. The total virtual capacity calculation is used to support hot spare space reservation, disk removal, rebuild of a failed disk, and to prevent over-commitment of storage to user data.