White Paper - Intel Intelligent Power Node Manager

While the components of a server system - processor, operating system, and so on - employ different
techniques to check power consumption, areas that could potentially help to reduce power
consumption are largely untapped.
1. Intel® processors and power management
Intel® processors support many features for power management. Prominent among them are demand
based switching using the Intel® SpeedStep® Technology and clock modulation.
Intel also provides other power efficiency techniques such as the following:
• Enhanced HALT state (C1E) or Turbo Mode
• Quad-Rank Fully Buffered DIMM (FB-DIMM)
• Closed Loop Thermal Throttling (CLTT)
The Intel® 5500 series processor (released in early Q1 09)
at runtime dynamically manages cores, threads,
cac
he, interfaces, and power to deliver outstanding energy efficiency and performance on demand.
For details on Intel® 5500 series processor po
wer efficiency design, refer to the paper “First the Tick, Now the Tock:
Next Generation Intel® Microa
rchitecture ”.
In addition, Intel is announcing the availability of yet another tool of Intel servers based on Intel® 5500 series
chipset using Intel® 5500 series processor. This tool is a management interface at the hands of an IT system
administrator, termed as the Intel® Node Manager (NM) Technology.
This whitepaper outlines the NM technology interface, the hardware required to exercise this
technology and application scenarios to make maximum use of NM in Intel® 5500 series chipset
servers. K
ey SMB use cases have also been addressed.
2. Overview of Node Manager
Node Manager (NM) is
a platform resident technology that enforces power and thermal policies
for the platform.
These policies are applied by exploiting processor subsystem knobs (such as
processor P and T states) that can be used to control power consumption. Node Manager enables
power and thermal management by exposing an external interface to management software through
which platform policies can be specified. It also implements specific data center power management
usage models such as power limiting. With the current implementation NM 1.5 only power control
policies are available.
To effectively manage power consumption in servers, NM exposes interfaces to measure input power
and platform consumed power at high CPU loads. A range of average power consumed at lowest loads
is available by a call to this interface. This value can then be used by the IT administrator set a power
policy budget. The policy interface of NM allows the following parameters to be set
1.
Power Budget: This specifies the power budget allocated to the node in watts.
2. Time limit – This specifies the time limit within which the server needs to operate at the budgeted
power limit. At the end of the time limit the server goes back to previous power consumption limit. This
time limit could be a recurring one based days of the week and a 24 hr time cycle
3.
Grace period –
4.
Power action – action to be taken when power threshold is crossed.
5.
power threshold value – user can set a power threshold value which when crossed will be used by NM
to take the action specified by the user