System and method for managing different types of snapshots of storage objects

Patent metadata

Field	Value
Publication number	US-10877849-B2
Application number	US-201816112703-A
Country	US
Kind code	B2
Filing date	Aug 25, 2018
Priority date	Aug 25, 2018
Publication date	Dec 29, 2020
Grant date	Dec 29, 2020

Abstract

System and method for managing different types of snapshots of storage objects stored in a storage system uses a storage structure that includes both a storage object and any snapshots of the storage object. When a request to delete a snapshot of the storage object is received, a determination is made whether the snapshot is a first snapshot type. After determining that the snapshot is not the first snapshot type, the snapshot is deleted from the storage structure. After determining that the snapshot is the first snapshot type, the snapshot is marked as delete designated, and a deletion of the snapshot from the storage structure is prevented when there is a second snapshot type snapshot remaining in the storage structure that was created after the snapshot had been created so that the snapshot is available when the second snapshot type snapshot is subsequently used.

First claim

What is claimed is:

1. A method for managing different types of snapshots of storage objects stored in a storage system, the method comprising:
receiving a request to delete a snapshot of a storage object, wherein the snapshot and the storage object are included in a storage structure in the storage system;
determining whether the snapshot is a first snapshot type or a second snapshot type, wherein a snapshot of the first snapshot type is a snapshot that is created in response to a user request and wherein a snapshot of the second snapshot type is a snapshot that is automatically created; and
when the snapshot is determined to be the second snapshot type, deleting the snapshot from the storage structure, and when the snapshot is determined to be the first snapshot type, marking the snapshot as delete designated without deleting the snapshot from the storage structure only if there is another snapshot of the second snapshot type in the storage structure and the another snapshot was created after the snapshot had been created in the storage structure, thereby the snapshot being available when the second snapshot type snapshot is subsequently used.

2. The method of claim 1 , wherein the first snapshot type is a type of snapshot created by a virtualization software supporting a virtual computing instance and wherein the second snapshot type snapshot is a snapshot created by a data protection module for recovery of the storage object.

3. The method of claim 1 , wherein the storage object and the snapshot are both stored in the storage structure using a B+ tree structure.

4. The method of claim 1 , further comprising, when the snapshot is determined to be the first snapshot type, marking the snapshot as delete designated, recording a deletion of the snapshot as an entry in the storage structure and deleting the snapshot from the storage structure if there is no snapshot of the second snapshot type that was created after the snapshot had been created in the storage structure.

5. The method of claim 1 , wherein each of the snapshot and the another snapshot is associated with a generation number that is increased from a previous generation number for a deletion or creation of any snapshot in the storage structure.

6. The method of claim 5 , wherein the storage structure includes at least an archive section, a metadata section and a data section, and wherein generation numbers of snapshots of the storage object are stored in the archive section of the storage structure.

7. The method of claim 1 , further comprising:
in response to a request to delete the another snapshot of the second snapshot type, deleting the another snapshot from the storage structure; and
when the snapshot that was previously delete designated without being deleted still exists in the storage structure, deleting the snapshot from the storage structure in response to the deletion of the another snapshot from the storage structure.

8. The method of claim 1 , wherein the storage object is a namespace object of a virtual machine or a virtual disk object of the virtual machine and the snapshot is a snapshot of the namespace object or the virtual disk object.

9. A computer-readable storage medium containing program instructions for managing different types of snapshots of storage objects stored in a storage system, wherein execution of the program instructions by one or more processors of a computer system causes the one or more processors to perform steps comprising:
receiving a request to delete a snapshot of a storage object, wherein the snapshot and the storage object are included in a storage structure in the storage system;
determining whether the snapshot is a first snapshot type or a second snapshot type, wherein a snapshot of the first snapshot type is a snapshot that is created in response to a user request and wherein a snapshot of the second snapshot type is a snapshot that is automatically created; and
when the snapshot is determined to be the second snapshot type, deleting the snapshot from the storage structure, and when the snapshot is determined to be the first snapshot type, marking the snapshot as delete designated without deleting the snapshot from the storage structure only if there is another snapshot of the second snapshot type in the storage structure and the another snapshot was created after the snapshot had been created in the storage structure, thereby the snapshot being available when the second snapshot type snapshot is subsequently used.

10. The computer-readable storage medium of claim 9 , wherein the first snapshot type is a type of snapshot created by a virtualization software supporting a virtual computing instance and wherein the second snapshot type snapshot is a snapshot created by a data protection module for recovery of the storage object.

11. The computer-readable storage medium of claim 9 , wherein the storage object and the snapshot are both stored in the storage structure using a B+ tree structure.

12. The computer-readable storage medium of claim 9 , wherein the steps further comprise, when the snapshot is determined to be the first snapshot type, marking the snapshot as delete designated, recording a deletion of the snapshot as an entry in the storage structure and deleting the snapshot from the storage structure if there is no snapshot of the second snapshot type that was created after the snapshot had been created in the storage structure.

13. The computer-readable storage medium of claim 9 , wherein each of the snapshot and the another snapshot is associated with a generation number that is increased from a previous generation number for a deletion or creation of any snapshot in the storage structure.

14. The computer-readable storage medium of claim 13 , wherein the storage structure includes at least an archive section, a metadata section and a data section, and wherein generation numbers of snapshots of the storage object are stored in the archive section of the storage structure.

15. The computer-readable storage medium of claim 9 , wherein the steps further comprise:
in response to a request to delete the another snapshot of the second snapshot type, deleting the another snapshot from the storage structure; and
when the snapshot that was previously delete designated without being deleted still exists in the storage structure, deleting the snapshot from the storage structure in response to the deletion of the another snapshot from the storage structure.

16. The computer-readable storage medium of claim 9 , wherein the storage object is a namespace object of a virtual machine or a virtual disk object of the virtual machine and the snapshot is a snapshot of the namespace object or the virtual disk object.

17. A computer system comprising:
a storage system having computer data storage devices to store at least one storage structure;
memory; and
a processor configured to:
receive a request to delete a snapshot of a storage object, wherein the snapshot and the storage object are included in a storage structure in the storage system;
determine whether the snapshot is a first snapshot type or a second snapshot type, wherein a snapshot of the first snapshot type is a snapshot that is created in response to a user request and wherein a snapshot of the second snapshot type is a snapshot that is automatically created; and
when the snapshot is determined to be the second snapshot type, delete the snapshot from the storage structure, and when the snapshot is determined to be the first snapshot type, mark the snapshot as delete designated without deleting the snapshot from the st

Assignees

• Vmware Inc

Inventors

• Desai Asit
• Uluski Derek
• Garthwaite Alexander T
• Satnur Sunil
• Languev Ilya
• Jaishankar Anoop

Classifications

• G06F16/2246

  Trees, e.g. B+trees · CPC title

• G06F16/128 Primary

  Details of file system snapshots on the file-level, e.g. snapshot creation, administration, deletion (error detection or correction of the data by redundancy in operations or in hardware G06F11/14, G06F11/16) · CPC title

• G06F11/1438

  Restarting or rejuvenating · CPC title

• G06F9/45558

  Hypervisor-specific management and integration aspects · CPC title

• G06F2201/84

  Using snapshots, i.e. a logical point-in-time copy of the data · CPC title