Compaq BL10e - HP ProLiant - 512 MB RAM Introduction Manual page 20

Calculator Utility shows for this configuration. Table 4 shows a summary of the power consumption
and capacity savings for the server group.
Table 4. Power consumption for eight DL380 G5 servers when capping to peak power consumption using basic
Power Capping
Description
Maximum possible power consumption for 8 DL380 G5 servers
(based on HP Power Calculator)
Maximum power consumption when capping to peak
Savings in power capacity
Additional servers that can be provisioned within the same cooling infrastructure
If all eight servers supported Dynamic Power Capping, the 3116 watt power cap could also be used
to manage electrical provisioning. Using traditional guidelines, these eight servers would require
7760 watts of provisioned power to support them. As Table 5 shows, if Dynamic Power Capping is
applied the same circuit can support over 11 more servers, assuming all are capped at the same
power levels as the first eight servers.
Table 5. Power provisioning for eight DL380 G5 servers when capping to peak power consumption using
Dynamic Power Capping
Description
Traditional input power provisioning for 8 DL380 G5 servers
(1217 input VA at 208 volts de-rated by 20 percent)
Maximum power consumption when capping to peak
Savings in power capacity
Additional servers that can be provisioned within same 7760 watts using Dynamic Power
Capping when capping to peak
When capping to peak based on the power consumption graph for a group of servers, it is important
to understand that we are actually capping to the peak of the sum of the power consumptions of the
servers in the group and then distributing that group cap as individual power caps for each server. It
is possible, especially if workloads on individual servers are peaking at different times or if workloads
vary significantly from server to server, that the individual power caps created for one or more servers
in the group may be lower than the individual peak power consumptions for those servers. This will
have an adverse affect on the performance of those servers, especially if they support Dynamic Power
Capping, since its faster monitoring will have greater impact on limiting transient peaks. HP
recommends that administrators using Dynamic Power Capping review the peak power consumption
of each server through IPM to ensure that the selected power cap for the server does not significantly
limit its actual peak power consumption.
Power
3384 watts
3116 watts
268 watts
0.7
Power
7760 watts
(970 x 8)
3116 watts
4645 watts
11.9
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