IBM Power 780 Technical Overview And Introduction page 132

automatically scans all pluggable PCI slots at regular intervals, looking for those that meet
the criteria for being not in use and powering them off. This support is available for all
POWER7 and POWER7+ processor-based servers and the expansion units that they
support.
Server power down
If overall data center processor utilization is low, workloads can be consolidated on fewer
numbers of servers so that some servers can be turned off completely. Consolidation
makes sense when there will be long periods of low utilization, such as weekends. AEM
provides information, such as the power that will be saved and the time needed to bring a
server back online, that can be used to help make the decision to consolidate and power
off. As with many of the features that are available in IBM Systems Director and Active
Energy Manager, this function is scriptable and can be automated.
Partition power management
Available with Active Energy Manager 4.3.1 or later, and POWER7 systems with the 730
firmware release or later, is the capability to set a power savings mode for partitions or the
system processor pool. As in the system-level power savings modes, the per-partition
power savings modes can be used to achieve a balance between the power consumption
and the performance of a partition. Only partitions that have dedicated processing units
can have a unique power savings setting. Partitions that run in shared processing mode
have a common power savings setting, which is that of the system processor pool. The
reason is because processing unit fractions cannot be power-managed.
As in the case of system-level power savings, two Dynamic Power Saver options are
offered:
– Favor partition performance
– Favor partition power savings
The user must configure this setting from Active Energy Manager. When dynamic power
saver is enabled in either mode, system firmware continuously monitors the performance
and utilization of each of the computer's POWER7 or POWE7+ processor cores that
belong to the partition. Based on this utilization and performance data, the firmware
dynamically adjusts the processor frequency and voltage, reacting within milliseconds to
adjust workload performance and also deliver power savings when the partition is
under-utilized.
In addition to the two dynamic power saver options, the customer can select to have no
power savings on a given partition. This option will leave the processor cores assigned to
the partition running at their nominal frequencies and voltages.
A power savings mode, referred to as
only to partitions. When configured to use this setting, a partition adopts the power
savings mode of its hosting server. By default, all partitions with dedicated processing
units, and the system processor pool, are set to the inherit host setting.
On POWER7 and POWER7+ processor-based systems, several EnergyScales are
imbedded in the hardware and do not require an operating system or external
management component. More advanced functionality requires Active Energy Manager
(AEM) and IBM Systems Director.
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IBM Power 770 and 780 (9117-MMD, 9179-MHD) Technical Overview and Introduction
inherit host setting
, is available and is applicable