6.5.1

Table Of Contents
Select a CPU Power Management Policy
You set the CPU power management policy for a host using the vSphere Web Client.
Prerequisites
Verify that the BIOS seings on the host system allow the operating system to control power management
(for example, OS Controlled).
N Some systems have Processor Clocking Control (PCC) technology, which allows ESXi to manage
power on the host system even if the host BIOS seings do not specify OS Controlled mode. With this
technology, ESXi does not manage P-states directly. Instead, the host cooperates with the BIOS to determine
the processor clock rate. HP systems that support this technology have a BIOS seing called Cooperative
Power Management that is enabled by default.
If the host hardware does not allow the operating system to manage power, only the Not Supported policy
is available. (On some systems, only the High Performance policy is available.)
Procedure
1 Browse to the host in the vSphere Web Client navigator.
2 Click .
3 Under Hardware, select Power Management and click the Edit buon.
4 Select a power management policy for the host and click OK.
The policy selection is saved in the host conguration and can be used again at boot time. You can
change it at any time, and it does not require a server reboot.
Configure Custom Policy Parameters for Host Power Management
When you use the Custom policy for host power management, ESXi bases its power management policy on
the values of several advanced conguration parameters.
Prerequisites
Select Custom for the power management policy, as described in “Select a CPU Power Management Policy,”
on page 24.
Procedure
1 Browse to the host in the vSphere Web Client navigator.
2 Click .
3 Under System, select Advanced System .
4 In the right pane, you can edit the power management parameters that aect the Custom policy.
Power management parameters that aect the Custom policy have descriptions that begin with In
Custom policy. All other power parameters aect all power management policies.
5 Select the parameter and click the Edit buon.
N The default values of power management parameters match the Balanced policy.
Parameter Description
Power.UsePStates
Use ACPI P-states to save power when the processor is busy.
Power.MaxCpuLoad
Use P-states to save power on a CPU only when the CPU is busy for less
than the given percentage of real time.
vSphere Resource Management
24 VMware, Inc.