System information

Dell
PowerEdge M1000e Technical Guide 33
Dell recommends that all customers running PowerEdge M910 blade servers should install the
modular iDRAC firmware 3.02 upgrade, which contains the following enhancements:
 Improved power budgeting to lower the amount of power budget that the M910 requests from
the CMC, enabling more servers to run on fewer power supplies.
 Functionality to enable iDRAC to retry power-ups for blade servers automatically in the event
that some servers do not power up initially due to the pre-boot power inventory.
Also, be aware that Dell recommends that all customers running M910 should install the modular
iDRAC firmware 3.02 upgrade. It contains several enhancements:
• Improved power budgeting to lower the amount of power budget M910 requests from the
CMC, enabling more servers to run on fewer power supplies
• Introduction of functionality to enable iDRAC to retry powering up of blade servers
automatically in the event some servers do not power up initially due to the pre-boot power
inventory
5.3 Power Management
Power is no longer just about power delivery, it is also about power management. The M1000e
system offers many advanced power management features. Most of these features operate
transparently to the user, while others require only a one time selection of desired operating modes.
Shared power takes advantage of the large number of resources in the modular server, distributing
power across the system without the excess margin required in dedicated rack mount servers and
switches. The M1000e has an advanced power budgeting feature, controlled by the CMC and
negotiated in conjunction with the iDRAC on every server module. Prior to any server module
powering up, through any of its power up mechanisms such as AC recovery, WOL or a simple power
button press, the server module iDRAC performs a sophisticated power budget inventory for the
server module, based upon its configuration of CPUs, memory, I/O and local storage. Once this
number is generated, the iDRAC communicates the power budget inventory to the CMC, which
confirms the availability of power from the system level, based upon a total chassis power inventory,
including power supplies, iKVM, I/O modules, fans, and server modules. Since the CMC controls when
every modular system element powers on, it can set power policies on a system level.
In coordination with the CMC, iDRAC hardware constantly monitors actual power consumption at
each server module. This power measurement is used locally by the server module to ensure that its
instantaneous power consumption never exceeds the budgeted amount. While the system
administrator may never notice these features in action, what they enable is a more aggressive
utilization of the shared system power resources. Thus the system is never flying blind in regards to
power consumption, and there is no danger of exceeding power capacity availability, which could
result in a spontaneous activation of power supply over current protection without these features.
The system administrator can also set priorities for each server module. The priority works in
conjunction with the CMC power budgeting and iDRAC power monitoring to ensure that the lowest
priority blades are the first to enter any power optimization mode, should conditions warrant the
activation of this feature.
Power capping is set at the chassis level for our blade servers and not at the blade server level, so
components like a processer or memory can throttle down when necessary on lower priority blade
servers. An allocation is taken out for a component (fans, I/O modules), the remainder is applied to
the blades, and then throttling is applied if required to get under the cap. If all the blades are set up
with the same priority, they will start throttling down the processor, memory, and so on. A variety of
BIOS settings will throttle the processor or not depending on load.