Recovering from a pending uncompleted reorganization of a data set

Patent metadata

Field	Value
Publication number	US-9298387-B2
Application number	US-201313944804-A
Country	US
Kind code	B2
Filing date	Jul 17, 2013
Priority date	Jul 17, 2013
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

Provided are a computer program product, system, and method for recovering from a pending uncompleted reorganization of a data set managing data sets in a storage. In response an initiation of an operation to access a data set, an operation is initiated to complete a pending uncompleted reorganization of the data set in response to the data set being in a pending uncompleted reorganization state and no other process currently accessing the data set.

First claim

What is claimed is:

1. A computer program product for managing data sets in a storage device, the computer program product comprising a computer readable storage medium including hardware having computer readable program code embodied therein that executes to perform operations, the operations comprising:
performing a reorganization operation of a data set comprising one of the data sets by setting information to indicate that the data set is empty and writing data from the data set to a temporary file to be written back to the data set;
indicating a pending uncompleted reorganization state for the data set in response to writing the data from the data set to the temporary file during the reorganization operation;
in response to an initiation of a computer implemented operation to access the data set in the storage device, initiating a computer implemented operation to complete a pending uncompleted reorganization of the data set in response to the data set being in the pending uncompleted reorganization state and no other computer process currently accessing the data set; and
in response to completing the pending uncompleted reorganization, setting the information to indicate an offset of a last written byte in the data set.

2. The computer program product of claim 1 , wherein the operations further comprise:
determining whether a reorganization flag indicates the pending uncompleted reorganization state, wherein the data set is in the pending uncompleted reorganization state if a reorganization operation started against the data set and was interrupted and did not complete, and wherein the operation to complete the pending uncompleted reorganization is initiated in response to determining that the reorganization flag indicates the pending uncompleted reorganization and that no other process is currently accessing the data set.

3. The computer program product of claim 2 , wherein the reorganization flag is set to indicate the pending uncompleted reorganization state during the reorganization operation.

4. The computer program product of claim 2 , wherein the operation to complete the pending uncompleted reorganization comprises:
writing the data from the data set in the temporary file back to the data set according to an ordering, wherein the reorganization flag is set to indicate the pending uncompleted reorganization state.

5. The computer program product of claim 4 , wherein the reorganization flag is set to indicate no pending uncompleted reorganization state in response to the writing of the data from the temporary file back to the data set.

6. The computer program product of claim 1 , wherein the writing the data from the data set to the temporary file is performed according to an ordering, wherein the operation to complete the pending uncompleted reorganization of the data set comprises:
determining a location of the temporary file; and
writing content of the temporary file to the data set.

7. The computer program product of claim 6 , wherein the location of the temporary file is indicated in data set record information for the data set as part of the reorganization operation.

8. The computer program product of claim 1 , wherein an exclusive lock is held against the data set if another process is accessing the data set to perform the reorganization operation of the data set, wherein the operations further comprise:
in response to initiating the operation to access the data set, waiting for a reorganization of the data set to complete in response to the data set being in the pending uncompleted reorganization state and one other process currently holding the lock to the data set.

9. A system for managing data sets in a storage device, comprising:
a processor;
a computer readable storage medium including hardware having computer readable program code embodied therein executable by the processor to perform operations, the operations comprising:
performing a reorganization operation of a data set comprising one of the data sets setting information to indicate that the data set is empty and by writing data from the data set to a temporary file to be written back to the data set;
indicating a pending uncompleted reorganization state for the data set in response to writing the data from the data set to the temporary file during the reorganization operation;
in response to an initiation of computer implemented operation to access the data set in the storage device, initiating a computer implemented operation to complete a pending uncompleted reorganization of the data set in response to the data set being in the pending uncompleted reorganization state and no other computer process currently accessing the data set; and
in response to completing the pending uncompleted reorganization, setting the information to indicate an offset of a last written byte in the data set.

10. The system of claim 9 , wherein the operations further comprise:
determining whether a reorganization flag indicates the pending uncompleted reorganization state, wherein the data set is in the pending uncompleted reorganization state if a reorganization operation started against the data set and was interrupted and did not complete, and wherein the operation to complete the pending uncompleted reorganization is initiated in response to determining that the reorganization flag indicates the pending uncompleted reorganization and that no other process is currently accessing the data set.

11. The system of claim 10 , wherein the operation to complete the pending uncompleted reorganization comprises:
writing the data from the data set in the temporary file back to the data set according to an ordering, wherein the reorganization flag is set to indicate the pending uncompleted reorganization state.

12. The system of claim 11 , wherein the reorganization flag is set to indicate no pending uncompleted reorganization state in response to the writing of the data from the temporary file back to the data set.

13. The system of claim 9 , wherein the writing the data from the data set to the temporary file is performed according to an ordering, wherein the operation to complete the pending uncompleted reorganization of the data set comprises:
determining a location of the temporary file; and
writing content of the temporary file to the data set.

14. The system of claim 9 , wherein an exclusive lock is held against the data set if another process is accessing the data set to perform the reorganization operation of the data set, wherein the operations further comprise:
in response to initiating the operation to access the data set, waiting for a reorganization operation of the data set to complete in response to the data set being in the pending uncompleted reorganization state and one other process currently holding the lock to the data set.

15. A computer implemented method for managing data sets in a storage device, comprising:
performing, by a processor, a reorganization operation of a data set comprising one of the data sets by setting information to indicate that the data set is empty and writing data from the data set to a temporary file to be written back to the data set;
indicating a pending uncompleted reorganization state for the data set in response to writing the data from the data set to the temporary file during the reorganization operation;
in response to an initiation of a computer implemented operation to access the data set in the storage device, initiating a computer implemented operation to complete a pending uncompleted reorganization of the data set in response to the data set being in the pending uncompleted reorgan

Assignees

• IBM

Inventors

• Chauvet Philip R
• House Charles J
• Reed David C
• Smith Max D

Classifications

• G06F3/0643 Primary

  Management of files · CPC title

• G06F16/215

  Improving data quality; Data cleansing, e.g. de-duplication, removing invalid entries or correcting typographical errors · CPC title

• G06F3/0689

  Disk arrays, e.g. RAID, JBOD · CPC title

• G06F16/23

  Updating · CPC title

• G06F16/1774 Primary

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