Providing unique inodes across multiple file system namespaces

• US 10,649,955 B2
• Filed: 01/03/2017
• Issued: 05/12/2020
• Est. Priority Date: 01/03/2017
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bhagwat, Deepavali M., Eshel, Marc, Hildebrand, Dean, Sawdon, Wayne A., Schmuck, Frank B.
• Primary Examiner(s): Gofman, Alex
• Assistant Examiner(s): Mian, Umar
• Application Number:
  US15/397,620
• Publication Number:
  US 20180189304A1
• Time in Patent Office: 1,225 Days
• Field of Search: None
• CPC Class Codes: G06F 16/13 File access structures, e.g. distributed indices arrangements of input from, or output to, record carriers G06F3/06
• CPC Class Codes: G06F 16/1727 Details of free space management performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• CPC Class Codes: G06F 16/188 Virtual file systems

Abstract

One embodiment provides a method for storage management in an aggregated file system. The method includes tracking inode numbers for sub-file systems of the aggregated file system. A request for a unique range of inode numbers in the aggregated file system is received. The unique range of inode numbers is provided to one or more sub-file systems of the aggregated file system while providing that each sub-file system of the aggregated file system has a required range of inode numbers and that no two sub-file systems have overlapping inode numbers.

Claims

1. A method for storage management in an aggregation file system, the method comprising:

tracking assigned inodes, inodes currently used by applications and a rate of inode requests for sub-file systems of the aggregation file system, wherein any sub-file system in a first aggregated file system environment is configurable as a top-file system portion of a second aggregated file system environment;

receiving a request for a unique range of inode numbers in the aggregation file system, wherein the request for the unique range of inode numbers is made from a top-file system portion or individual sub-file systems of the aggregated file system, each sub-file system of the aggregated file system consumes a flexible range of inode numbers, and a namespace in the top file system portion of the aggregation file system and pointers to the sub-file systems include a name of a directory in a particular sub-file system that is its inode number in the top file system portion;

providing the unique range of inode numbers to sub-file systems of the aggregated file system while providing that each sub-file system of the aggregated file system has a required, flexible and unique range of inode numbers and that no two sub-file systems have overlapping inode numbers;

determining that a particular sub-file system requires more inode numbers;

revoking one or more inode numbers from one or more other sub-file systems; and

allocating the revoked inode numbers to the particular sub-file system.

2. The method of claim 1, wherein tracking the rate of inode requests comprises:

determining an inode request rate for each sub-file system requesting additional inode number ranges; and

upon a determination that an inode request rate exceeds a predetermined threshold, issuing additional inode number ranges based on a number of inode requests.

3. The method of claim 1, further comprising receiving an update of number of used inode numbers from each sub-file system.

4. The method of claim 3, further comprising:

revoking a portion of unused inode numbers from sub-file systems having more unused inode numbers than other sub-file systems based on updates from each of the sub-file systems.

5. The method of claim 1, wherein each sub-file system waits to request more inode number ranges based on comparing a number of unused inode numbers to a predetermined threshold.

6. The method of claim 1, wherein each sub-file system tracks respective assigned inode numbers and number of inode numbers that are currently used by one or more applications.

7. The method of claim 1, further comprising:

receiving a query from the top-file system portion for determining sub-file system inode number consumption for a particular sub-file system; and

based on a number of used inode numbers, migrating data along with a namespace and an inode for the data from the particular sub-file system to another sub-file system without handling inode number collisions and maintaining unique inode numbers across all sub-file systems.

8. A computer program product for storage management in an aggregated file system, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable by a processor to cause the processor to:

track, by the processor, assigned inodes, inodes currently used by applications and a rate of inode requests for sub-file systems of the aggregated file system, wherein any sub-file system in a first aggregated file system environment is configurable as a top-file system portion of a second aggregated file system environment;

receive, by the processor, a request for a unique range of inode numbers in the aggregated file system, wherein the request for the unique range of inode numbers is made from a top-file system portion or individual sub-file systems of the aggregated file system, each sub-file system of the aggregated file system consumes a flexible range of inode numbers, and a namespace in the top file system portion of the aggregation file system and pointers to the sub-file systems include a name of a directory in a particular sub-file system that is its inode number in the top file system portion;

provide, by the processor, the unique range of inode numbers to sub-file systems of the aggregated file system while providing that each sub-file system of the aggregated file system has a required, flexible and unique range of inode numbers and that no two sub-file systems have overlapping inode numbers;

determine, by the processor, that a particular sub-file system requires more inode numbers;

revoke, by the processor, one or more inode numbers from one or more other sub-file systems; and

allocate, by the processor, the revoked inode numbers to the particular sub-file system.

9. The computer program product of claim 8, wherein tracking the rate of inode requests comprises:

determining an inode request rate for each sub-file system requesting additional inode number ranges; and

upon a determination that an inode request rate exceeds a predetermined threshold, issuing additional inode number ranges based on a number of requests.

10. The computer program product of claim 8, further comprising program instructions executable by the processor to cause the processor to:

receive, by the processor, an update of number of used inode numbers from each sub-file system; and

revoke, by the processor, a portion of unused inode numbers from sub-file systems having more unused inode numbers than other sub-file systems based on updates from each of the sub-file systems.

11. The computer program product of claim 8, further comprising program instructions executable by the processor to cause the processor to:

receive, by the processor, a query from the top-file system portion for determining sub-file system inode number consumption for a particular sub-file system; and

based on a number of used inode numbers, migrating, by the processor, data along with a namespace and an inode for the data from the particular sub-file system to another sub-file system without handling inode number collisions and maintaining unique inode numbers across all sub-file systems.

12. An apparatus comprising:

a memory storing instructions; and

one or more processors executing the instructions to;

track assigned inodes, inodes currently used by applications and a rate of inode requests-for sub-file systems of the aggregated file system, wherein any sub-file system in a first aggregated file system environment is configurable as a top-file system portion of a second aggregated file system environment;

receive a request for a unique range of inode numbers in the aggregated file system, wherein the request for the unique range of inode numbers is made from a top-file system portion or individual sub-file systems of the aggregated file system, each sub-file system of the aggregated file system consumes a flexible range of inode numbers, and a namespace in the top file system portion of the aggregation file system and pointers to the sub-file systems include a name of a directory in a particular sub-file system that is its inode number in the top file system portion;

provide the unique range of inode numbers to sub-file systems of the aggregated file system while providing that each sub-file system of the aggregated file system has a required, flexible and unique range of inode numbers and that no two sub-file systems have overlapping inode numbers;

determine that a particular sub-file system requires more inode numbers;

revoke one or more inode numbers from one or more other sub-file systems; and

allocate the revoked inode numbers to the particular sub-file system.

13. The apparatus of claim 12, wherein tracking the rate of inode requests comprises the one or more processors further executing instructions to:

determine an inode request rate for each sub-file system requesting additional inode number ranges; and

upon a determination that an inode request rate exceeds a predetermined threshold, issue additional inode number ranges based on a number of requests.

14. The apparatus of claim 12, wherein the processor further executes instructions to:

receive an update of number of used inode numbers from each sub-file system; and

revoke a portion of unused inode numbers from sub-file systems having more unused inode numbers than other sub-file systems based on updates from each of the sub-file systems.

15. The apparatus of claim 12, wherein the processor further executes instructions to:

receive a query from the top-file system portion for determining sub-file system inode number consumption for a particular sub-file system; and

based on a number of used inode numbers, migrate data along with a namespace and an inode for the data from the particular sub-file system to another sub-file system without handling inode number collisions and maintaining unique inode numbers across all sub-file systems.