Data set index record preservation

• US 8,918,400 B2
• Filed: 02/19/2013
• Issued: 12/23/2014
• Est. Priority Date: 07/02/2010
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Reed, David C., Smith, Max D., Belisle, Jon C.
• Primary Examiner(s): TRUONG, CAM Y T
• Application Number:
  US13/770,036
• Publication Number:
  US 20130159258A1
• Time in Patent Office: 672 Days
• Field of Search: 707/741, 707/674
• US Class Current: 707/741
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 11/1446 Point-in-time backing up or restoration of persistent data
• CPC Class Codes: G06F 16/22 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/23 Updating

Abstract

Portions of index information are pulled from a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory. The name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members. Pursuant to an update to the PDSE data sets, a selected portion of an index record of the dataset is stored as a record in the new subindex data set and the storing includes acting on an integrated catalog facility catalog to perform operations relating to allowacation and maintenance of the new subindex data set. An oldest existing record is replaced with a recent version if a determination is made that adding the recent version exceeds a predetermined number of versions. A component of the new subindex data set is recoverable.

Claims

1. A method for preserving data set information in a computing storage environment by a processor device, comprising:

pulling portions of index information from a basic catalog structure (BCS) of an integrated catalog facility (ICF) catalog, the BCS pointing to multiple virtual storage access method (VSAM) volume data sets (VVDS) including a volume table of contents (VTOC) and including a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory, the name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members, and the new subindex data set being associated with the PDSE data sets via a catalog entry;

pursuant to an update to the PDSE data sets, storing at least one portion of selected portions of an index record of the dataset as a record in the new subindex data set, wherein the step of storing at least one portion includes acting on the ICF catalog to perform operations relating to allocation and maintenance of the new subindex data set;

replacing an oldest existing record with a most recent version if a determination is made that adding the most recent version exceeds a predetermined number of versions, wherein at least one component of the new subindex data set is recoverable into the index record in an event of an error detected within the index record;

including referring to the new subindex data set to determine a historical change of an index comprising at least the index record to discover the source of an index corruption, in an event the index is corrupted; and

including referring to extent location and size field data in the new subindex data set to determine the historical change of the index comprising at least the index record from reviewing each version of the predetermined number of versions to discover the source of an index corruption.

2. The method of claim 1, further including pulling the at least one portion of the selected portions from the index record.

3. The method of claim 1, further including combining a name and a last update field of the index record as a key of the record in the new subindex data set.

4. The method of claim 3, further including combining an extent location and a size field of the index record as data of the record in the new subindex data set.

5. The method of claim 4, further comprising obtaining the name, the extent location, and the size field from the name directory, and the last update field from the name directory.

6. The method of claim 1, further including, pursuant to an update of the index record, performing at least one of updating the at least one component of the subindex data set and storing the at least one portion of the selected portions of the index record as an additional version of the at least one component of the subindex data set.

7. The method of claim 1, further including associating the new subindex data set with the PDSE data sets via a catalog entry.

8. The method of claim 1, further comprising regenerating portions of the index from the data of records in the new subindex data set to allow a user continued access to the data, in an event the index is corrupted.

9. A system for preserving data set information in a computing storage environment, comprising:

at least one processor device;

a memory including a data set module controlled by the at least one processor device operational in the computing storage environment, wherein the data set module;

pulls portions of index information from a basic catalog structure (BCS) of an integrated catalog facility (ICF) catalog, the BCS pointing to multiple virtual storage access method (VSAM) volume data sets (VVDS) including a volume table of contents (VTOC) and including a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory, the name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members, and the new subindex data set being associated with the PDSE data sets via a catalog entry,

pursuant to an update to the PDSE data sets, stores at least one portion of selected portions of an index record of the dataset as a record in the new subindex data set, wherein the step of storing at least one portion includes acting on the ICF catalog to perform operations relating to allocation and maintenance of the new subindex data set,

replaces an oldest existing record with a most recent version if a determination is made that adding the most recent version exceeds a predetermined number of versions, wherein at least one component of the new subindex data set is recoverable into the index record in an event of an error detected within the index record; and

include referring to the new subindex data set to determine a historical change of an index comprising at least the index record to discover the source of an index corruption, in an event the index is corrupted;

include referring to extent location and size field data in the new subindex data set to determine the historical change of the index comprising at least the index record from reviewing each version of the predetermined number of versions to discover the source of an index corruption.

10. The system of claim 9, wherein the data set module pulls the at least one portion of the selected portions from the index record.

11. The system of claim 9, wherein the data set module combines a name and a last update field of the index record as a key of the record in the new subindex data set.

12. The system of claim 11, wherein the data set module combines an extent location and a size field of the index record as data of the record in the new subindex data set.

13. The system of claim 12, wherein the data set module comprises obtaining the name, the extent location, and the size field from the name directory, and the last update field from the name directory.

14. The system of claim 9, wherein the data set module, pursuant to an update of the index record, performs at least one of updating the at least one component of the subindex data set and storing the at least one portion of the selected portions of the index record as an additional version of the at least one component of the subindex data set.

15. The system of claim 9, wherein the data set module associates the new subindex data set with the PDSE data sets via a catalog entry.

16. The system of claim 9, wherein the data set module regenerates portions of the index from the data of the records in the new subindex data set to allow a user continued access to the data, in an event the index is corrupted.

17. A computer program product preserving data set information in a computing storage environment, the computer program product comprising a non-transitory computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

a first executable portion that pulls portions of index information from a basic catalog structure (BCS) of an integrated catalog facility (ICF) catalog, the BCS pointing to multiple virtual storage access method (VSAM) volume data sets (VVDS) including a volume table of contents (VTOC) and including a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory, the name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members, and the new subindex data set being associated with the PDSE data sets via a catalog entry;

a second executable portion that pursuant to an update to the PDSE data sets, stores at least one portion of selected portions of an index record of the dataset as a record in the new subindex data set, wherein the step of storing at least one portion includes acting on the ICF catalog to perform operations relating to allocation and maintenance of the new subindex data set;

a third executable portion that replaces an oldest existing record with a most recent version if a determination is made that adding the most recent version exceeds a predetermined number of versions, wherein at least one component of the new subindex data set is recoverable into the index record in an event of an error detected within the index record;

a fourth executable portion that refers to the new subindex data set to determine a historical change of an index comprising at least the index record to discover the source of an index corruption, in an event the index is corrupted; and

a fifth executable portion that refers to extent location and size field data in the new subindex data set to determine the historical change of the index comprising at least the index record from reviewing each version of the predetermined number of versions to discover the source of an index corruption.

18. The computer program product of claim 17, further including a fourth executable portion that pulls the at least one portion of the selected portions from the index record.

19. The computer program product of claim 17, further including a fourth executable portion that combines a name and a last update field of the index record as a key of the record in the new subindex data set.

20. The computer program product of claim 19, further including a fifth executable portion that combines an extent location and a size field of the index record as data of the record in the new subindex data set.

21. The computer program product of claim 20, further including a sixth executable portion that obtains the name, the extent location, and the size field from the name directory, and the last update field from the name directory.

22. The computer program product of claim 17, further including a fourth executable portion that, pursuant to an update of the index record, performs at least one of updating the at least one component of the subindex data set and storing the at least one portion of the selected portions of the index record as an additional version of the at least one component of the subindex data set.

23. The computer program product of claim 17, further including a fourth executable portion that associates the new subindex data set with the PDSE data sets via a catalog entry.

24. The computer program product of claim 17, further including a fourth executable portion that regenerates portions of the index from the data of the records in the new subindex data set to allow a user continued access to the data, in an event the index is corrupted.