HP Insight Control Software for Linux - Manual (Page 56)

If the power requirements for the system slightly exceed the power or thermal capacity within the chosen
rack, you can configure power capping to this system and others in the rack to ensure all get the necessary
resources, without wasted allocation. If you are deploying a system, you apply the cap value to the enclosure
that will include the system to ensure the power capacity of the power delivery devices and thermal capacity
of the rack are not exceeded. Then, insert the system in the enclosure. The cap value is divided among the
other systems in the enclosure. If it is not a system, you must determine the number of watts required by the
new system. You can use the HP Power Calculator, or more accurately start the system and determine its
Calibrated Max Power. You can obtain this value from the Power/Thermal Analysis views or Power/Thermal
data report pages of power management. You can also obtain the value from the Power Management
Settings page of the system’s iLO page, where it is mentioned as Sever Maximum Power, as shown below:
Then, determine the amount of power must be reclaimed to make the necessary power/thermal capacity
available in the rack.
When applying caps, use the following guidelines:
1. As the power demand varies, Enclosure Dynamic Power Capping can share caps between systems, it
is the first place to investigate when capping and there is typically significant capacity that can be
reclaimed by applying caps to enclosures.
2. If you have multiple enclosures, reclaim similar percentages of capacity of the headroom from each
enclosure instead of a large amount of headroom from a single enclosure.
3. When applying power cap value to individual systems, you need to be careful not to impact their
performance because of increase in load beyond the historically observed loads result in reduced
performance. Again, reclaiming a small percentage of capacity from multiple systems is preferable and
less likely to have a significant impact on performance.
4. When reclaiming power delivery capacity, you must ensure not to remove or increase power cap values
without proper planning as it could lead to overload of the circuit capacity.
Task: Classifying systems by business criticality
Based on business criticality, you can classify systems using the Customize Collections option of HP Systems
Insight Manager. The systems that you want to classify are controlled by the collections in the Systems by
Service Class
group. You can find the collections under Systems > Shared > Systems by Service Class
in the System and Event Collections tree view from the left pane of the Systems Insight Manager home
page.
To add service classes and remove or rename existing service classes, use the Customize... option at the
top of the tree view to change the set of collections within Systems by Service Class.
To classify a system, use the Customize... option to add the system to the collection for its service class.
56 Managing power and cooling facilities in your data center