Introduction

Building servers that are energy efficient and sustainable is a crucial requirement, not only for customers but also for a better use of environmental resources. The energy consumed to power and cool the servers has a significant role in customer business. In the range of IBM Power11 baseboard management controller (BMC) platforms, the new approach to bring the energy efficiency is achieved with the help of new power mode option that is energy efficient.

The BMC power modes enable admins to optimize energy consumption, perform maintenance, and ensure high availability on need basis.

This tutorial explains the various power modes offered by BMC and describes how and when to configure the required power mode.

BMC power modes

The BMC provides the following power and performance modes

Energy efficient
Maximum performance
Maximum energy saver

Energy efficient

Refer to the following list to understand more about the energy efficient mode.

This is the new power mode introduced for Power11 BMC platforms.
For this particular power mode, the frequency remains between the maximum and the mid-range frequency.
This mode functions based on the workload of the system and will adjust by increasing the frequency when higher workload is running.
Processor folding concept works to adjust the processors based on the workload of the system.

Note: Processor folding is a power-management technique that helps systems to activate or deactivate processors based on the workload demand and thus optimize energy consumption (refer: https://www.ibm.com/support/pages/processor-folding-policy-shared-and-dedicated-partitions).

Maximum performance

Refer to the following list to understand more about the maximum performance mode.

Choose this mode for a fully functioning workload.
It is the default power mode set for the BMC and uses the maximum frequency. In case of heavy workload, this power mode is the most favourable mode to handle optimal functionality of the system.
In this mode, the processor folding concept ensures to put all the processors function at maximum performance.

Maximum energy saver

Refer to the following list to understand more about the maximum energy saver mode.

Choose this power mode when the system is functioning on a reduced workload.
In this power mode, the system runs at a lower frequency to save power and still delivers predictable performance.
Also, it lowers the processor frequency and voltage to a minimum value resulting in reduced power consumption.
The processor folding concept puts few of the processors to go to an idle state and the system functionality keeps running with the minimum required processors.

Configure power modes using the BMC GUI

Perform the following steps to set the power modes on the BMC GUI:

Log in to the BMC GUI with your user credentials.
On the Overview page, view the details in the Power information section (as shown in the following screenshot).

Note: The default power mode is Maximum performance.
To select the required power mode, click Resource Management → Power.

On the Power page, in the Power and performance modes section, before selecting a mode, you can check the View effects of each mode option to understand the behavior of each power mode.

Then select the required mode and click Update power saver mode.

Note: The power mode can be set even when the system is running or is on the standby mode.
After selecting the option, confirm the setting in the dialog box that is displayed. The selected power mode is applied immediately.

Configure power modes using the Redfish API

Perform the following steps to configure the power modes using the Redfish API:

Get the current power mode:

curl -k -H "X-Auth-Token: <bmc_token>" -X GET https://<BMC_IP>/redfish/v1/Systems/system | grep -A4 PowerMode

Set the required power mode.

Refer to the following commands for each power mode option:

Energy efficient:

curl -k -H "Content-Type: application/json" -H "X-Auth-Token: <bmc_token>"  -X PATCH -d '{ "PowerMode": “EfficiencyFavorPower”}' https://<BMC_IP>/redfish/v1/Systems/system

Maximum performance:

curl -k -H "Content-Type: application/json" -H "X-Auth-Token: <bmc_token>"  -X PATCH -d '{ "PowerMode": “MaximumPerformance”}' https://<BMC_IP>/redfish/v1/Systems/system

Maximum energy saver:

curl -k -H "Content-Type: application/json" -H "X-Auth-Token: <bmc_token>"  -X PATCH -d '{ "PowerMode": “PowerSaving”}' https://<BMC_IP>/redfish/v1/Systems/system

Conclusion

IBM Power11 BMC platforms now offer three power modes—Energy efficient, maximum performance, and maximum energy saver—to enhance energy efficiency and reduce environmental impact. These modes enable users to optimize energy consumption and server performance based on workload, using techniques such as processor folding. This tutorial provided guidance to users to configure the required power mode using the BMC GUI or the Redfish API to meet their workload requirements.

Enhance energy efficiency in enterprise baseboard management controller (eBMC) based IBM Power11 systems