PDSE extended generation grouping for tiered storage systems

Patent metadata

Field	Value
Publication number	US-9927989-B2
Application number	US-201514929360-A
Country	US
Kind code	B2
Filing date	Nov 1, 2015
Priority date	Nov 1, 2015
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A method for storing data includes establishing an extended generation group comprising a plurality of data sets. The plurality of data sets include a first data set containing primary members and a first number of generations of each of the primary members, and a second data set containing a second number of generations of each of the primary members. The first data set and the second data set are stored on different tiers of a tiered storage system, and may even be stored on different volumes. The first data set may be stored on higher performance storage media and the second data set may be stored on lower performance storage media. Additionally, the second number will typically be greater than the first number so that more generations are stored on lower performance storage media. A corresponding system and computer program product are also disclosed.

First claim

The invention claimed is:

1. A method for storing data, the method comprising:
establishing an extended generation group comprising a plurality of data sets, the plurality of data sets comprising a first data set containing primary members and a first number of generations of each of the primary members, and a second data set containing a second number of generations of each of the primary members, wherein the first data set and the second data set are stored on different tiers of a tiered storage system;
indicating, in metadata of the first data set, that the first data set and the second data set are associated with the extended generation group;
indicating, in the metadata of the first data set, a maximum number of generations allowable in each of the first data set and the second data set; and
providing, in the metadata of the first data set, a root directory that provides a starting point to locate generations in each of the first data set and the second data set.

2. The method of claim 1 , wherein, for each primary member, the generations in the second data set are older than the generations in the first data set.

3. The method of claim 1 , wherein the second number is greater than the first number.

4. The method of claim 3 , wherein the second number is a multiple of the first number.

5. The method of claim 1 , further comprising providing, in each of the first data set and the second data set, a type flag that indicates whether the associated data set includes primary members or generations only.

6. The method of claim 1 , further comprising storing the first and second data sets on different volumes.

7. The method of claim 1 , further comprising providing, in metadata of the second data set, a branch directory that enables generations to be located and retrieved from within the second data set.

8. A computer program product for storing data, the computer program product comprising a computer-readable medium having computer-usable program code embodied therein, the computer-usable program code comprising:
computer-usable program code to establish an extended generation group comprising a plurality of data sets, the plurality of data sets comprising a first data set containing primary members and a first number of generations of each of the primary members, and a second data set containing a second number of generations of each of the primary members, wherein the first data set and the second data set are stored on different tiers of a tiered storage system;
computer-usable program code to indicate, in metadata of the first data set, that the first data set and the second data set are associated with the extended generation group;
computer-usable program code to indicate, in the metadata of the first data set, a maximum number of generations allowable in each of the first data set and the second data set; and
computer-usable program code to provide, in the metadata of the first data set, a root directory that provides a starting point to locate generations in each of the first data set and the second data set.

9. The computer program product of claim 8 , wherein, for each primary member, the generations in the second data set are older than the generations in the first data set.

10. The computer program product of claim 8 , wherein the second number is greater than the first number.

11. The computer program product of claim 10 , wherein the second number is a multiple of the first number.

12. The computer program product of claim 8 , further comprising computer-usable program code to provide, in each of the first data set and the second data set, a type flag that indicates whether the associated data set includes primary members or generations only.

13. The computer program product of claim 8 , further comprising computer-usable program code to store the first and second data sets on different volumes.

14. The computer program product of claim 8 , further comprising computer-usable program code to provide, in metadata of the second data set, a branch directory that enables generations to be located and retrieved from within the second data set.

15. A system for storing data, the system comprising:
at least one processor;
at least one memory device operably coupled to the at least one processor and storing instructions for execution on the at least one processor, the instructions causing the at least one processor to:
establish an extended generation group comprising a plurality of data sets, the plurality of data sets comprising a first data set containing primary members and a first number of generations of each of the primary members, and a second data set containing a second number of generations of each of the primary members, wherein the first data set and the second data set are stored on different tiers of a tiered storage system;
indicate, in metadata of the first data set, that the first data set and the second data set are associated with the extended generation group;
indicate, in the metadata of the first data set, a maximum number of generations allowable in each of the first data set and the second data set; and
provide, in the metadata of the first data set, a root directory that provides a starting point to locate generations in each of the first data set and the second data set.

16. The system of claim 15 , wherein, for each primary member, the generations in the second data set are older than the generations in the first data set.

17. The system of claim 15 , wherein the second number is a multiple of the first number.

18. The system of claim 15 , wherein the instructions further cause the at least one processor to provide, in each of the first data set and the second data set, a type flag that indicates whether the associated data set includes primary members or generations only.

19. The system of claim 15 , wherein the instructions further cause the at least one processor to store the first and second data sets on different volumes.

20. The system of claim 15 , wherein the instructions further cause the at least one processor to provide, in metadata of the second data set, a branch directory that enables generations to be located and retrieved from within the second data set.

Assignees

• IBM

Inventors

• Erdmann Derek L
• Reed David C
• Reed Thomas C
• Smith Max D

Classifications

• G06F3/0619 Primary

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/0665

  at area level, e.g. provisioning of virtual or logical volumes · CPC title

• G06F3/0689

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

• G06F3/0685

  Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays · CPC title

• G06F3/0631

  by allocating resources to storage systems · CPC title