[54] METHOD FOR PERFORMING ON-LINE RECONFIGURATION OF A DISK ARRAY CONCURRENT WITH EXECUTION OF DISK VO OPERATIONS
[75] Inventor: Dale F. Rathunde, Wheaton, 111.
[73] Assignees: AT&T Global Information Solutions
Company, Dayton, Ohio; Hyundai
Electronics America, Milpitas, Calif.;
Symbios Logic Inc., Fort Collins, Colo.
[21] Appl. No.: 482,425
[22] Filed: Jun. 7, 1995
Related U.S. Application Data
[63] Continuation of Ser. No. 48,248, Apr. 19, 1993, abandoned.
[51] Int. CI.6 G06F 11/00; G06F 12/00
[52] U.S. CI 395/182.05; 395/404; 395/492;
364/242.31; 364/243; 364/245; 364/263.3;
364/268.3; 364/DIG. 1
[58] Field of Search 395/800, 575,
395/425, 400, 275, 500, 825, 828, 404, 439, 497.01, 182.05, 182.06, 183.16, 492; 371/8.1, 10.1, 11.1, 21.1, 40.1, 51.1, 67.1,
48
[56] References Cited
U.S. PATENT DOCUMENTS
5,166,936 11/1992 Ewertetal 371/21.6
5,210,860 5/1993 Pfefferetal 395/575
An architecture for on-line reconfiguration on a RAID level 0, 1, 2, 3, 4 or 5 disk array. This architecture allows the computer system to perform reconfiguration of the disk array transparently, with disk I/O operations being performed concurrently with reconfiguration operations. The reconfiguration process allocates computer system resources necessary to support both the old and new array configurations during the reconfiguration process. Logical areas within the array are sequentially reconfigured from the old configuration to the new configuration. Data in each logical area is read from the area undergoing reconfiguration and thereafter overwritten in accordance with the new array configuration. System I/O requests received during reconfiguration which are directed to unreconfigured areas in the disk array are executed in accordance with the old array configuration. System I/O requests received during reconfiguration which are directed to reconfigured areas in the disk array are executed in accordance with the new array configuration.
11 Claims, 9 Drawing Sheets
