Method and system for dynamic allocation of buffer storage space during backup copying

• US 5,379,412 A
• Filed: 04/20/1992
• Issued: 01/03/1995
• Est. Priority Date: 04/20/1992
• Status: Expired due to Term

• Current Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Ratliff, James M., Eastridge, Lawrence E.
• Primary Examiner(s): Chan, Eddie P.
• Application Number:
  US07/871,373
• Time in Patent Office: 988 Days
• Field of Search: 395/575, 395/425, 395/250, 395/650
• US Class Current: 711/162
• CPC Class Codes: G06F 11/1466 to make the backup process non-disruptive

Abstract

A method and system for the dynamic allocation of a buffer storage space during backup copying. Backup copying of designated datasets representing point in time consistency may be performed in a data processing system on one or more storage subsystems concurrent with data processing system application execution by suspending execution only long enough to form a logical to physical address concordance and thereafter physically backing up the datasets on the storage subsystems on a scheduled or opportunistic basis. A particular area of an established buffer storage space is dynamically allocated for each designated dataset to be backed up. The designated datasets are then stored in the particular areas and indexed. After all designated datasets to be backed up are copied to an alternate storage subsystem location, the buffer storage space is released.

Claims

1. A method in a data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system, said method comprising the data processing system implemented steps of:

suspending said application execution within said data processing system, forming a dataset logical-to-physical storage system address concordance for said plurality of designated datasets and resuming said application execution thereafter;

establishing a buffer storage space within said data processing system, wherein said buffer storage space includes a plurality of areas;

determining a number of all of said plurality of designated datasets to be utilized for backup copying and dynamically allocating a particular one of said plurality of areas of said buffer storage space for each of said number of all of said plurality of designated datasets;

physically backing up said plurality of designated datasets within said one or more storage subsystems on a scheduled or opportunistic basis utilizing said dataset logical-to-physical storage system address concordance by copying each of said plurality of designated datasets from said one or more storage subsystems to a particular one of said plurality of areas and indexing each of said copied plurality of designated datasets;

processing at said one or more storage subsystems any updates initiated by said application to uncopied datasets among said plurality of designated datasets by temporary buffering said updates within said storage subsystem, writing as sidefiles said plurality of designated datasets or portions thereof affected by said updates within said storage subsystem, and writing said buffered updates to said one or more storage subsystems;

copying each of said plurality of designated datasets affected by said updates from said sidefiles to a particular one of said plurality of areas of said buffer storage space and indexing each of said copied plurality of designated datasets affected by said updates;

copying all of said plurality of designated datasets from all of said plurality of areas to an alternate storage subsystem location; and

releasing said buffer storage space in response to all of said plurality of designated datasets being copied from all of said plurality of areas to said alternate storage subsystem location.

2. The method in a data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 1, further comprising the step of deleting all of said plurality of designated datasets from all of said plurality of areas in response to all of said plurality of designated datasets being copied from all of said plurality of areas to said alternate storage subsystem location.

3. The method in a data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 1, wherein said buffer storage space is established within an extended memory within said data processing system.

4. The method in a data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 1, wherein each of said plurality of areas is sufficient to store one dataset.

5. A data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system, comprising:

means for suspending said application execution within said data processing system, forming a dataset logical-to-physical storage system address concordance for said plurality of designated datasets and resuming said application execution thereafter;

means for establishing a buffer storage space within said data processing system, wherein said buffer storage space includes a plurality of areas;

means for determining a number of all of said plurality of designated datasets to be utilized for backup copying and dynamically allocating a particular one of said plurality of areas of said buffer storage space for each of said number of all of said plurality of designated datasets;

means for physically backing up said plurality of designated datasets within said one or more storage subsystems on a scheduled or opportunistic basis utilizing said dataset logical-to-physical storage system address concordance by copying each of said plurality of designated datasets from said one or more storage subsystems to a particular one of said plurality of areas and indexing each of said copied plurality of designated datasets;

means for processing at said one or more storage subsystems any updates initiated by said application to uncopied datasets among said plurality of designated datasets by temporary buffering said updates within said storage subsystem, writing as sidefiles said plurality of designated datasets or portions thereof affected by said updates within said storage subsystem, and writing said buffered updates to said one or more storage subsystems;

means for copying each of said plurality of designated datasets affected by said updates from said sidefiles to a particular one of said plurality of areas of said buffer storage space and indexing each of said copied plurality of designated datasets affected by said updates;

means for copying all of said plurality of designated datasets from all of said plurality of areas to an alternate storage subsystem location; and

means for releasing said buffer storage space in response to all of said plurality of designated datasets being copied from all of said plurality of areas to said alternate storage subsystem location.

6. The data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 5, further comprising means for deleting all of said plurality of designated datasets from all of said plurality of areas in response to all of said plurality of designated datasets being copied from all of said plurality of areas to said alternate storage subsystem location.

7. The data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 5, wherein said buffer storage space is established within an extended memory within said data processing system.

8. The data processing system for backup copying of a plurality of designated datasets stored within one or more storage subsystems coupled to said data processing system during application execution within said data processing system according to claim 5, wherein each of said plurality of areas is sufficient to store one dataset.