SELECTING A HOST FROM A HOST CLUSTER FOR LIVE MIGRATION OF A VIRTUAL MACHINE

• US 20100332657A1
• Filed: 06/29/2009
• Published: 12/30/2010
• Est. Priority Date: 06/29/2009
• Status: Active Grant

• Current Assignee: Red Hat Israel Ltd. (International Business Machines Corporation)
• Original Assignee: Red Hat Israel Ltd. (International Business Machines Corporation)
• Inventors: Elyashev, Vitaly, Frenkel, Omer
• Granted Patent: US 8,489,744 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers

Abstract

A host controller migrates live virtual machines from one host to another host to balance the load in the host cluster. In one embodiment, the host controller identifies an overloaded host from the host cluster. The host controller selects a virtual machine from the existing virtual machines that run on the overloaded host based on a percentage value associated with the virtual machine. The percentage value represents CPU usage incurred by the virtual machine on the host. In one embodiment, the selected virtual machine is one that incurs the least amount of load on the host. The host controller then selects a target host from the host cluster as a destination for migrating the selected virtual machine.

Claims

1. A computer-implemented method comprising:

identifying, by a host controller, an overloaded host running a plurality of virtual machines in a host cluster that includes a plurality of hosts;

selecting, by the host controller, one of the virtual machines based on a corresponding percentage value representing CPU usage incurred by each virtual machine; and

selecting, by the host controller, a target host from the host cluster to migrate the virtual machine from the overloaded host to the target host.

2. The method of claim 1, wherein selecting one of the virtual machines further comprises:

selecting the virtual machine that incurs the least amount of load on the target host with respect to the CPU usage.

3. The method of claim 1, wherein selecting a target host further comprises:

identifying a low utilization host in the host cluster by determining whether the low utilization host has CPU utilization below a low CPU utilization border continuously for a pre-determined time period; and

selecting the low utilization host as the target host.

4. The method of claim 1, wherein identifying an overloaded host further comprises:

determining the overloaded host as a host having CPU utilization above a high CPU utilization border continuously for a pre-determined time period.

5. The method of claim 1, wherein selecting a target host further comprises:

selecting the target host based on average CPU utilization per core and the number of cores on the target host.

6. The method of claim 1, wherein selecting a target host further comprises:

selecting the target host based on a configurable value chosen by a user to indicate a strength of the target host.

7. The method of claim 1, further comprising:

identifying an under-loaded host in the host cluster based on a CPU utilization level in comparison with a deactivation threshold; and

in response to a determination that the under-loaded host is to be powered-off, redistributing load of the under-loaded host to other active hosts in the host cluster.

8. A computer readable storage medium including instructions that, when executed by a processing system, cause the processing system to perform a method comprising:

identifying an overloaded host running a plurality of virtual machines in a host cluster that includes a plurality of hosts;

selecting one of the virtual machines based on a corresponding percentage value representing CPU usage incurred by each virtual machine; and

selecting a target host from the host cluster to migrate the virtual machine from the overloaded host to the target host.

9. The computer readable storage medium of claim 8, wherein selecting one of the virtual machines further comprises:

selecting the virtual machine that incurs the least amount of load on the target host with respect to the CPU usage.

10. The computer readable storage medium of claim 8, wherein selecting a target host further comprises:

identifying a low utilization host in the host cluster by determining whether the low utilization host has CPU utilization below a low CPU utilization border continuously for a pre-determined time period; and

selecting the low utilization host as the target host.

11. The computer readable storage medium of claim 8, wherein identifying an overloaded host further comprises:

determining the overloaded host as a host having CPU utilization above a high CPU utilization border continuously for a pre-determined time period.

12. The computer readable storage medium of claim 8, wherein selecting a target host further comprises:

selecting the target host based on average CPU utilization per core and the number of cores on the target host.

13. The computer readable storage medium of claim 8, wherein selecting a target host further comprises:

selecting the target host based on a configurable value chosen by a user to indicate a strength of the target host.

14. The computer readable storage medium of claim 8, further comprising:

identifying an under-loaded host in the host cluster based on a CPU utilization level in comparison with a deactivation threshold; and

in response to a determination that the under-loaded host is to be powered-off, redistributing load of the under-loaded host to other active hosts in the host cluster.

15. A host controller coupled to a host cluster that includes a plurality of hosts to run virtual machines, the host controller comprising:

a virtual machine selection module to select one of the virtual machines based on a corresponding percentage value representing CPU usage incurred by each virtual machine; and

a host selection module to identify an overloaded host in the host cluster, and to select a target host from the host cluster to migrate the virtual machine from the overloaded host to the target host.

16. The host controller of claim 15, wherein the host controller includes a load balancer that runs a background process to migrate the virtual machines.

17. The host controller of claim 15, wherein the host controller selects the virtual machine that incurs the least amount of load on the target host with respect to the CPU usage.

18. The host controller of claim 15, wherein the host controller selects a low utilization host as the host, the low utilization host having CPU utilization that below a low CPU utilization border continuously for a pre-determined time period, and in response to a determination that more than one low utilization host exists in the host cluster, the host controller to select the host target based on average CPU utilization per core and the number of cores on the target host.

19. The host controller of claim 15, wherein the host controller determining the overloaded host as a host having CPU utilization above a high CPU utilization border continuously for a pre-determined time period.

20. The host controller of claim 15, wherein the host controller powers off an under-loaded host that has a utilization level lower than a deactivation threshold, and redistributes load of the under-loaded host to other active hosts in the host cluster.