Methods and systems for creating and removing virtual machine snapshots based on groups of metrics

Patent metadata

Field	Value
Publication number	US-9442937-B2
Application number	US-201514752329-A
Country	US
Kind code	B2
Filing date	Jun 26, 2015
Priority date	Aug 29, 2014
Publication date	Sep 13, 2016
Grant date	Sep 13, 2016

Abstract

Techniques are described herein which minimize the impact of virtual machine snapshots on the performance virtual machines and hypervisors. In the context of a volume snapshot which may involve (i) taking virtual machine snapshots of all virtual machines associated with the volume, (ii) taking the volume snapshot, and (iii) removing all the virtual machine snapshots, the virtual machine snapshots may be created in a first order and removed in a second order. Specifically, snapshots for busy virtual machines (i.e., virtual machines with higher disk write activity) may be created last and removed first. Consequently, snapshots of busy virtual machines are retained for the shorter periods of time, thereby minimizing the effect of virtual machine snapshots on those virtual machines (and their associated hypervisors) that would be most negatively impacted by virtual machine snapshots.

First claim

What is claimed is:

1. A method for creating and removing snapshots of a plurality of virtual machines instantiated on a host, all of the virtual machines storing data on a volume of a storage system communicatively coupled to the host, the method comprising:
receiving by a hypervisor manager a first request to create snapshots of all of the virtual machines associated with the volume so as to maintain a state of each of the virtual machines, wherein the first request includes a first order of the virtual machines, and the first order is based on a first group of one or more metrics associated with the virtual machines;
instructing by the hypervisor manager one or more hypervisors instantiated on the host to create, via a plurality of snapshot creation operations, the snapshots of all of the virtual machines associated with the volume, wherein the virtual machine snapshot creation operations are initiated in the first order;
subsequent to the storage system taking a snapshot of the volume, receiving by the hypervisor manager a second request to remove the snapshots of all of the virtual machines associated with the volume, wherein the second request includes a second order of the virtual machines, the second order is based on a second group of one or more metrics associated with the virtual machines, and at least one metric from the second group does not belong to the first group, wherein the at least one metric from the second group that does not belong to the first group comprises, for each of the virtual machines, a disk write activity of the virtual machine during the snapshot of the volume; and
instructing by the hypervisor manager one or more of the hypervisors to remove, via a plurality of snapshot removal operations, the snapshots of all of the virtual machines associated with the volume, wherein the virtual machine snapshot removal operations are initiated in the second order, and wherein the removal of all the virtual machine snapshots associated with the volume occurs without removal of the volume snapshot.

2. The method of claim 1 , wherein the first group of metrics include, for each of the virtual machines, a disk write activity of the virtual machine prior to the creation of the snapshot of the virtual machine.

3. The method of claim 1 , wherein the second group of metrics include, for each of the virtual machines, one or more of a disk write activity of the virtual machine prior to the creation of the snapshot of the virtual machine, a disk write activity of the virtual machine after the creation of the virtual machine snapshot and before the removal of the virtual machine snapshot, a time taken to create the virtual machine snapshot, and a size of a child disk associated with the virtual machine.

4. The method of claim 3 , wherein the at least one metric from the second group that does not belong to the first group further comprises the time taken to create the virtual machine snapshot.

5. The method of claim 3 , wherein the at least one metric from the second group that does not belong to the first group further comprises the size of the child disk associated with the virtual machine.

6. The method of claim 1 , wherein the first and second requests are received from the storage system.

7. A server for creating and removing snapshots of a plurality of virtual machines instantiated on a host, all of the virtual machines storing data on a volume of a storage system communicatively coupled to the host, the server comprising:
a main memory;
a processor communicatively coupled to the main memory; and
software instructions on the main memory that, when executed by the processor, cause the processor to:
receive a first request to create snapshots of all of the virtual machines associated with the volume so as to maintain a state of each of the virtual machines, wherein the first request includes a first order of the virtual machines, and the first order is based on a first group of one or more metrics associated with the virtual machines;
instruct one or more hypervisors instantiated on the host to create, via a plurality of snapshot creation operations, the snapshots of all of the virtual machines associated with the volume, wherein the virtual machine snapshot creation operations are initiated in the first order;
subsequent to the storage system taking a snapshot of the volume, receive a second request to remove the snapshots of all of the virtual machines associated with the volume, wherein the second request includes a second order of the virtual machines, the second order is based on a second group of one or more metrics associated with the virtual machines, and at least one metric from the second group does not belong to the first group, wherein the at least one metric from the second group that does not belong to the first group comprises, for each of the virtual machines, a disk write activity of the virtual machine during the snapshot of the volume; and
instruct one or more of the hypervisors to remove, via a plurality of snapshot removal operations, the snapshots of all of the virtual machines associated with the volume, wherein the virtual machine snapshot removal operations are initiated in the second order, and wherein the removal of all the virtual machine snapshots associated with the volume occurs without removal of the volume snapshot.

8. The server of claim 7 , wherein the first group of metrics include, for each of the virtual machines, a disk write activity of the virtual machine prior to the creation of the snapshot of the virtual machine.

9. The server of claim 7 , wherein the second group of metrics include, for each of the virtual machines, one or more of a disk write activity of the virtual machine prior to the creation of the snapshot of the virtual machine, a disk write activity of the virtual machine after the creation of the virtual machine snapshot and before the removal of the virtual machine snapshot, a time taken to create the virtual machine snapshot, and a size of a child disk associated with the virtual machine.

10. The server of claim 9 , wherein the at least one metric from the second group that does not belong to the first group further comprises the time taken to create the virtual machine snapshot.

11. The server of claim 9 , wherein the at least one metric from the second group that does not belong to the first group further comprises the size of the child disk associated with the virtual machine.

12. The server of claim 7 , wherein the first and second requests are received from a storage system on which data of the virtual machines is stored.

13. A non-transitory machine-readable storage medium for creating and removing snapshots of a plurality of virtual machines instantiated on a host, all of the virtual machines storing data on a volume of a storage system communicatively coupled to the host, the non-transitory machine-readable storage medium comprising software instructions that, when executed by a processor of a server, cause the server to:
receive a first request to create snapshots of the virtual machines associated with the volume so as to maintain a state of each of the virtual machines, wherein the first request includes a first order of the virtual machines, and the first order is based on a first group of one or more metrics associated with the virtual machines;
instruct one or more hypervisors instantiated on the host to create, via a plurality of snapshot creation operations, the snapshots of all of the virtual machines associated with the volume, wherein the virtual machine snapshot creation operations are initiated in the first order;
subsequent to the storage system taking a snapshot of the

Assignees

• Nimble Storage Inc

Inventors

• Chelur Raja Shekar
• Wang Juhsun
• Ranganathan Gaurav

Classifications

• G06F9/45558 Primary

  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

• G06F2009/45562

  Creating, deleting, cloning virtual machine instances · CPC title

• G06F3/0689

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

• G06F2009/45575

  Starting, stopping, suspending or resuming virtual machine instances · CPC title