How to Configure Virtual Machine Priority and Availability
Updated: October 21, 2008
Applies To: Virtual Machine Manager 2008, Virtual Machine Manager 2008 R2, Virtual Machine Manager 2008 R2 SP1
You can configure how CPU or memory resources are allocated and whether the virtual machine is highly available. You can use these procedures when you modify a virtual machine or template, or configure hardware profile settings from the New Template Wizard, the New Hardware Profile Wizard or the New Virtual Machine Wizard.
To configure the priority for how memory resources are allocated, you must be running Virtual Machine Manager 2008 R2 with Service Pack 1. For the memory priority setting to take effect, the virtual machine must be placed on a Hyper-V host that is running Windows Server 2008 R2 with Service Pack 1 (SP1).
|To modify the memory priority setting of an existing virtual machine, the virtual machine must be hosted on a Hyper-V server that is running Windows Server 2008 R2 with SP1.|
When CPU or memory usage on a host is high, virtual machines with higher priority are allocated CPU or memory resources before virtual machines with lower priority. You can select a priority or assign a custom priority to exercise finer control.
|Memory priority affects the startup order of virtual machines that are configured to use static memory or the Dynamic Memory feature. If a virtual machine is configured to use Dynamic Memory, memory priority is also used to determine how memory is allocated to running virtual machines. For more information about the requirements for Dynamic Memory, see What's New in Virtual Machine Manager 2008 R2 SP1.|
To configure a virtual machine's priority for using host CPU or memory resources
In the left pane, under Advanced, click Priority.
In the results pane, select one of the following settings for CPU or memory resources, and then click OK:
Custom. Use this field to fine-tune the relative priority of CPU or memory resources that are given to the virtual machine. For CPU, the default value is 1 (the lowest priority) and the highest setting is 10,000. For memory, the default value is 5,000 (normal priority), the lowest setting is 0 (low priority), and the highest setting is 10,000 (high priority).
Warning If you specify a low priority for memory resource allocation, this may prevent the virtual machine from starting when other virtual machines are running and available memory is low. Be aware that a higher priority virtual machine will start before a lower priority virtual machine.
Making a virtual machine highly available will allow you to run the virtual machine on clustered Hyper-V hosts.
To configure a virtual machine as a highly available virtual machine
In the left pane, under Advanced, click Availability.
In the right pane, select Make this VM highly available.
During placement, only Hyper-V hosts that are in a failover cluster and ESX hosts in a host cluster with High Availability enabled will be available for this virtual machine.