Apparatus and methods for copying, backing up and restoring logical objects in a computer storage system by transferring blocks out of order or in parallel

• US 6,920,537 B2
• Filed: 07/17/2002
• Issued: 07/19/2005
• Est. Priority Date: 12/31/1998
• Status: Expired due to Term

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Bitner, Haim, Kedem, Nadav, Krikler, Samuel, Cakeljic, Zoran, Arnon, Dan, Hirsch, Michael, Ofek, Yuval, Galtzur, Sharon
• Primary Examiner(s): Vital, Pierre M.
• Application Number:
  US10/196,867
• Publication Number:
  US 20030061456A1
• Time in Patent Office: 1,098 Days
• Field of Search: 711112-114, 711/162, 711/165, 711/202, 707/200, 707/204, 707/205
• US Class Current: 711/163
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

Method and apparatus are disclosed for copying and backing up logical objects in a computer storage system. The logical objects are comprised of data blocks. The data blocks may be copied in any order. The data blocks may be copied or written from a storage media, such as a tape, in parallel.

Claims

1. A method of copying a logical object, the logical object including logical data blocks stored in a plurality of storage segments of a first computer storage device, the logical data blocks being arranged in a logical order within the logical object, the method comprising steps of:

identifying a set of the storage segments that includes the logical data blocks;

copying to a second computer storage device the logical data blocks stored in the identified storage segments, a plurality of the logical data blocks stored in the storage segments being copied in parallel; and

providing metadata to the second computer storage device identifying the logical order of the logical data blocks in the logical object.

2. The method of claim 1, wherein the storage segment size is a fixed size block corresponding in size to a size of the logical data blocks.

3. The method of claim 1, wherein the storage segment size is a track size of a disk of the first computer storage device.

4. A method of backing up a logical object including a plurality of logical blocks having a logical order in the logical object, comprising steps of:

providing a first backup media;

providing a second backup media;

writing the logical blocks to the first backup media and the second backup media in parallel; and

writing information relating to the logical order of the logical blocks in the logical object to at least one of the first and second backup media.

5. The method of claim 4, wherein the first backup media is a first tape and the second backup media is a second tape.

6. The method of claim 4, wherein the step of writing information relating to the logical order of the logical blocks in the logical object comprises writing metadata to distinguish a location in the logical object of each of the written logical blocks.

7. The method of claim 6, wherein the step of writing metadata comprises a step of writing the metadata on each of the first backup media and the second backup media.

8. The method of clalm 6, wherein the metadata comprises:

a plurality of labels, each label associated with one or more of the data blocks; and

a table associating the labels with a relative position in the logical object.

9. The method of clalm 6, wherein the metadata comprises physical memory addresses corresponding to the location of logical data blocks of the logical object stored in a primary storage device.

10. The method of claim 9, wherein the metadata comprises:

a physical address associated with an extent of physical data blocks storing the logical data blocks, and

a table specifying the relative position of the extents in the logical object.

11. A secondary storage device, comprising:

a plurality of storage components; and

means for writing an abstract block set to a plurality of the storage components, in parallel, the abstract block set including information relating to an order of logical data blocks in a logical object.

12. The secondmy storage device of claim 11, wherein the storage components are tapes.

13. A secondary storage device, comprising:

means for reading data from a plurality of storage components in parallel; and

means for providing the read data to another device as an abstract block set, the abstract block set including information relating to an order of logical data blocks in a logical object.