Dell PowerEdge 1655MC - Manual (Page 16)

Optimal BIOS settings for HPC with Dell PowerEdge 12 th generation servers
16
5.1. Idle power
Very few clusters tend to be fully utilized, i.e., running load at all times on all the servers. Most
clusters have some downtime when all or part of the cluster is not being used, and this is where
idle power usage is relevant. If there is anticipated downtime for a cluster, when the load is
expected to be light or close to zero, the cluster can be configured to save power while it is idle.
For this exercise, the power consumption of the 16-node test cluster was measured when the
servers were idle and there was no load on the servers.
Figure 3. Idle power usage across different System Profiles
* Data collected on a 16-server PowerEdge M620 cluster. Dual Intel Xeon E5-2680 @ 2.7GHz, 8*8GB
1600MT/s memory per server. Mellanox InfiniBand FDR.
Figure 3 presents data for idle power consumption of the four default System Profiles. The baseline
used for the graphs is the power consumption of the DAPC System Profile. From the results it is
seen that the cluster idle power consumption is similar with the DAPC- and OS-based profiles. The
Performance profile consumes 19% more idle power, which is not unusual since this profile disables
C States and C1E, two power savings BIOS options. The Dense profile consumes 3% less power than
DAPC; this is attributed to the memory’s operating at a lower speed. The Dense profile configures
the system memory to run at 1333MT/s, one bin less than the maximum possible of 1600MT/s for
this cluster.
1.00 1.01
1.19
0.97
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
PerfPerWattOptimizedDapc PerfPerWattOptimizedOs Perf Optimzed DenseCfgOptimized
Idl
e
P
o
w
er
R
elati
ve
t
o
DA
P
C
Idle Power - default system profiles