IBM Support

Change Power Management settings

Technote (FAQ)


Question

How to change power management settings from HMC?

Answer

You can enable the power saver mode on a managed system to reduce power consumption of the processors. this feature reduces power consumption by adjusting downward the processor voltage and clock frequency. This setting only takes effect when the server firmware is at standby or running.
If disabled, the processor voltage and clock frequency will be set to their nominal values, and the power consumed by the system will remain at a nominal level as well.

Follow the steps below based on the UI in use:

From Classic UI:

In the navigation area, expand Systems management.
In the navigation area, expand Servers.
Select the server that you want to enable to use power saver mode.
In the Tasks area, expand Operations.
Click Power Management.
Select your desired power saver mode, and click OK.

From Enhanced+ UI:

In the navigation area, Select Resources, then All systems and select the server
From Actions, select View All Actions, under Operations, select Power Management




From ASMI:

Launch Advanced System Management, expand System Configuration, select Power Management Mode Setup




From HMC Command Line:

You can set the desired power-saving mode from the command line interface and in order to run the pwrmgmt commands from the HMC, the userID must has (hmcsuperadmin) role.

You can list all managed system names, by running:
# lssyscfg -r sys -F name

The user can list which power management modes are supported using the lspwrmgmt command on the command line as illustrated below:
# lspwrmgmt -m <managed system name> -r sys -F supported_power_saver_mode_types

Example output:
"static,dynamic_favor_power,dynamic_favor_perf,fixed_max_frequency"

A user can then enable one of the supported power management modes using the chpwrmgmt command on the command line as illustrated below enabling Fixed Maximum Frequency mode:

# chpwrmgmt -m <managed system name> -r sys -o enable -t fixed_max_frequency

To query the current power management mode use lspwrmgmt command on the command line as illustrated below:

# lspwrmgmt -m <managed system name> -r sys

Example output:
curr_power_saver_mode=Enabled,curr_power_saver_mode_type=fixed_max_frequency,desired_power_saver_mode=Enabled,desired_power_saver_mode_type=fixed_max_frequency,”supported_power_saver_mode_types=static,dynamic_favor_power,dynamic_favor_perf,fixed_max_frequency”

NOTE: The new mode may not take effect immediately. Normally, if the operation is performed before the system is powered on, the desired mode won't take effect until the system is up and running. If the mode is in transition, any changes will be blocked.

To disable power management mode:
# chpwrmgmt -m <managed system name> -r sys -o disable

Related information

IBM white paper IBM EnergyScale for POWER8 Processor-Ba

Cross reference information
Segment Product Component Platform Version Edition
Operating System AIX

Document information

More support for: AIX family

Software version: Not Applicable

Operating system(s): AIX

Reference #: T1025318

Modified date: 19 February 2018