By Sridevi Chandrasekaran and Shonn Burton

 

Dell’s advanced power management feature on 12G PowerEdge servers offers advanced power capping options. Blade level power capping helps to reduce cost by limiting peak power consumption during a specified time period. For example, a company’s email server can be set to a particular lower power cap value for the weekends. On blade servers, power capping capabilities are available not only at the blade chassis level but also at the server level and data center level.

Server level power capping can be set using the iDRAC7 web interface or CLI (either RACADM or WS-MAN).  An iDRAC7 Enterprise license is required for blade level power capping functionality.

Dell’s Open Manage Power Center (OMPC) provides a graphical user interface that allows you to set power caps at the rack, aisle and/or datacenter level.

 

Server level power capping is an improvement over previous generations of PowerEdge blade servers, as 11G blade servers are limited to Chassis level power capping.

Setting Power Cap value

On 12G blades the power cap can be set at several levels.  Dell provides a recommended range of power values, depending on your system configuration.  You can set a power cap value depending on your need for performance or power savings.

  • If you set a power cap value within a recommended range then iDRAC7 will not request a power allocation from CMC above the power cap value you specified.
  • If you set a power cap value below the recommended range then iDRAC7 may not be able to maintain the power cap and will request at least a minimum threshold level of power allocation from CMC.   
  • If you try to set a power cap value above the recommended range then iDRAC7 will display a warning message and will not allow you to set that value.

Additionally, a power cap alert function sends out a notification if the user-defined power cap limit cannot be maintained.

Using OMPC, the servers in a data center can be grouped physically and or logically. In case of an emergency, such as a brownout, you can enable the Emergency Power Reduction feature on a predefined physical or logical group. This feature allows for maximum power throttling on specific groups of servers to minimize power consumption.  

 

For more details about power capping on Dell PowerEdge 12th Generation blade servers, refer to the whitepapers below:

             Power and Cooling Innovations

             Power Efficiency

             SPEC benchmark performance

            OMPC Whitepaper

  

For more information about Open Manage Power Center, visit:

            OpenManage Power Center page on Dell TechCenter