Providing record-level alternate-index upgrade locking

Patent metadata

Field	Value
Publication number	US-9710479-B2
Application number	US-201514703820-A
Country	US
Kind code	B2
Filing date	May 4, 2015
Priority date	Mar 15, 2013
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

In one embodiment, a method includes receiving a request to perform an update on a base data set in a record-oriented file system, wherein one or more affected records within the base data set are modified by the update. Affected alternate index (AIX) records corresponding to the affected records are located, and individual record-level locks are acquired on each affected AIX record. Each of the affected AIX records is updated according to the update after acquiring the individual record-level locks on each of the affected AIX records.

First claim

What is claimed is:

1. A method, comprising:
receiving a request to perform an update on a base data set in a record-oriented file system, wherein one or more affected records within the base data set are modified by the update;
locating affected alternate index (AIX) records corresponding to the affected records;
acquiring individual record-level locks on each affected AIX record;
holding the individual record-level locks on each of the affected AIX records only during updating of the affected AIX records; and
updating each of the affected AIX records according to the update after acquiring the individual record-level locks on each of the affected AIX records,
wherein the affected AIX records are updated in parallel with updating of unaffected AIX records, and
wherein the individual record-level locks on each of the affected AIX records each include a resource name comprising a x ‘16’ byte key value hash.

2. The method as recited in claim 1 , wherein the file system is a virtual storage access method (VSAM) system, and wherein the AIX is defined over an entry sequenced data set (ESDS).

3. The method as recited in claim 1 , comprising updating unaffected AIX records in parallel with the updating of the affected AIX records, wherein individual record-level locks are not acquired for all AIX records included in the base data set, and wherein an overall upgrade lock is not acquired on all AIX records included in the base data set.

4. The method as recited in claim 1 , comprising obtaining a record-level lock for the base data set prior to updating the base data set, wherein input/output (I/O) for the base data set and the affected AIX records are chained together, wherein a key sequenced data set (KSDS) provides an index for the base data set, and wherein the KSDS is keyed to a different field of the base data set than the AIX.

5. The method as recited in claim 1 , comprising relinquishing the individual record-level locks on all of the affected AIX records after updating of the affected AIX records is complete.

6. The method as recited in claim 1 , comprising relinquishing a first record-level lock on a first affected AIX record after updating of the first affected AIX record is complete.

7. The method as recited in claim 1 , comprising:
acquiring a lock on the base data set prior to updating the base data set;
acquiring a lock on an entry sequenced data set (ESDS) for the base data set when the individual record-level locks are acquired on the affected AIX records; and
serializing updates to the base data set with updates on the affected AIX records.

8. The method as recited in claim 1 , wherein at least some of the AIX records include an alternate key field along with one or more relative byte address (RBA) values when the base data set is an entry sequenced data set (ESDS), wherein each RBA value corresponds to a record in the base data set.

9. The method as recited in claim 1 , wherein at least some of the AIX records include one or more primary keys when the base data set is a key sequenced data set (KSDS), wherein each primary key corresponds to a record in the base data set.

10. A computer program product for updating alternate index (AIX) records, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions being at least one of readable and executable by a computer to cause the computer to:
receive, using the computer, a request to perform an update on a base data set in a record-oriented file system, wherein one or more affected records within the base data set are modified by the update;
locate, using the computer, affected AIX records corresponding to the affected records;
acquire, using the computer, individual record-level locks on each affected AIX record;
hold, using the computer, the individual record-level locks on each of the affected AIX records only during updating of the affected AIX records; and
update, using the computer, each of the affected AIX records according to the update after acquiring the individual record-level locks on each of the affected AIX records,
wherein the affected AIX records are updated in parallel with updating of unaffected AIX records, and
wherein the individual record-level locks on each of the affected AIX records each include a resource name comprising a x ‘16’ byte key value hash.

11. The computer program product as recited in claim 10 , wherein the file system is a virtual storage access method (VSAM) system, and wherein the AIX is defined over at least one of a key sequenced data set (KSDS) and an entry sequenced data set (ESDS).

12. The computer program product as recited in claim 10 , with the proviso that an upgrade lock is not acquired for all of the AIX records for the base data set.

13. The computer program product as recited in claim 10 , wherein a key sequenced data set (KSDS) provides an index for the base data set, and wherein the KSDS is keyed to a different field of the base data set than the AIX.

14. The computer program product as recited in claim 10 , wherein the program instructions are configured to cause the computer to relinquish the individual record-level locks on the affected AIX records after updating the affected AIX records, wherein the affected AIX records are updated in parallel with updating of unaffected AIX records.

15. The computer program product as recited in claim 10 , wherein the program instructions are configured to cause the computer to relinquish a first record-level lock on a first affected AIX record after updating the first affected AIX record.

16. The computer program product as recited in claim 10 , wherein the program instructions are configured to cause the computer to hold record-level locks on affected AIX records only during updating of the affected AIX records.

17. The computer program product as recited in claim 11 , wherein the program instructions are configured to cause the computer to:
acquire a lock on the base data set prior to updating the base data set;
acquire a lock on the ESDS or the KSDS for the base data set when the individual record-level locks are acquired on the affected AIX records; and
serialize updates to the base data set with updates to the affected AIX records.

18. A system, comprising:
a processor and logic that is at least one of integrated and executable by the processor, the logic being configured to cause the processor to perform a method comprising:
receiving a request to perform an update on a base data set in a record-oriented file system, wherein one or more affected records within the base data set are modified by the update;
locating affected alternate index (AIX) records corresponding to the affected records;
acquiring individual record-level locks on each affected AIX record;
holding the individual record-level locks on each of the affected AIX records only during updating of the affected AIX records; and
updating each of the affected AIX records according to the update after acquiring the individual record-level locks on each of the affected AIX records,
wherein the affected AIX records are updated in parallel with updating of unaffected AIX records, and
wherein the individual record-level locks on each of the affected AIX records each include a resource name comprising a x ‘16’ byte key value hash.

19. The system as recited in claim 18 , wherein the file system is a virtual storage access method (VSAM) system, and wherein the AIX is defined over at least one of a key sequenced data

Assignees

• IBM

Inventors

• Benjamin-Deckert Debra J
• Law Lawrence L
• Menendez Terri A

Classifications

• G06F16/2365

  Ensuring data consistency and integrity · CPC title

• G06F16/1774 Primary

  Locking methods, e.g. locking methods for file systems allowing shared and concurrent access to files · CPC title

• G06F16/23

  Updating · CPC title

• G06F16/188

  Virtual file systems · CPC title

• G06F17/30233

  Physics · mapped topic