Dynamic redistribution of parity groups

• US 6,862,692 B2
• Filed: 01/29/2002
• Issued: 03/01/2005
• Est. Priority Date: 01/29/2001
• Status: Expired due to Term

• Current Assignee: Braodband Storage LLC, Overland Storage Incorporated (Silicon Valley Technology Partners LLC)
• Original Assignee: Adaptec Incorporated (Steel Partners Holdings LP)
• Inventors: Schweitzer, James R., Bolstad, Gregory D., Staub, John R., Randall, Jay G., Ulrich, Thomas R., Priester, George W.
• Primary Examiner(s): PEIKARI, BEHZAD
• Application Number:
  US10/060,874
• Publication Number:
  US 20020194526A1
• Time in Patent Office: 1,127 Days
• Field of Search: 711/111, 711/112, 711/114, 711/161, 711/162, 714/5, 714/6, 714/7, 714/8
• US Class Current: 714/6.12
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 2211/1004 Adaptive RAID, i.e. RAID system adapts to changing circumstances, e.g. RAID1 becomes RAID5 as disks fill up
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

A system and method for dynamic redistribution of parity groups is described. The system and method for dynamic redistribution of parity groups operates on a computer storage system that includes a plurality of disk drives for storing parity groups. Each parity group includes storage blocks. The storage blocks include one or more data blocks and a parity block that is associated with the data blocks. Each of the storage blocks is stored on a separate disk drive such that no two storage blocks from a given parity set reside on the same disk drive. The computer system further includes a redistribution module to dynamically redistribute parity groups by combining some parity groups to improve storage efficiency.

Claims

1. A computer storage system comprising:

a plurality of disk drives for storing parity groups, each parity group comprising storage blocks, said storage blocks comprising one or more data blocks and a parity block associated with said one or more data blocks, each of said storage blocks stored on a separate disk drive such that no two storage blocks from a given parity group reside on the same disk drive;

a redistribution module to dynamically redistribute parity groups by combining some parity groups to improve storage efficiency; and

metadata that specifies at least one Gnid-string, wherein said Gnid-string comprises a collection of gnids, wherein each of said gnids comprises information for locating a specified gnode.

2. The computer storage system of claim 1, wherein said information for locating a specified gnode comprises a pointer to said specified gnode.

3. The computer storage system of claim 1, wherein said specified gnode comprises file attributes for a file corresponding to said gnode.

4. The computer storage system of claim 1, wherein said file attributes include at least one of a file id, a file access time, a file creation time, and a file modification time.

5. The computer storage system of claim 1, wherein said specified gnode comprises information for locating a first gee of a plurality of gees corresponding to said gnode.

6. The computer storage system of claim 5, wherein said plurality of gees comprises gnode gees and data gees.

7. The computer storage system of claim 6, wherein each of said gnode gees comprises information to specify an extent.

8. The computer storage system of claim 6, wherein each of said data gees comprises information to specify a first logical disk block and information to specify which of said disk drives contains said first logical block.

9. The computer storage system of claim 6, wherein said plurality of gees further comprises parity gees.

10. The computer storage system of claim 9, wherein each of said parity gees comprises information regarding location of parity data for one or more preceding data gees in said plurality of gees.

11. The computer storage system of claim 5, wherein a parity group comprises a first set of one or more data gees and an associated parity gee.

12. The computer storage system of claim 11, wherein each data gee identifies a block of data and said parity gee identifies a parity block.