Copyright by William Lloyd Bircher 2010 - The Laboratory for ...

Watts
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CPU
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gamess
h264ref
hmmer
calculix
namd
povray
gromacs
perlbench
gobmk
dealII
sjeng
tonto
xalancbmk
cactusADM
bzip2
Average
astar
gcc
sphinx3
wrf
bwaves
zeusmp
leslie3d
omnetpp
GemsFDTD
soplex
mcf
libquantum
milc
lbm
Figure 4.4 SPEC CPU2006 Average Core vs. DIMM Power
4.1.3 Desktop Platform – SYSmark 2007
In this section average power consumption levels across a range of workloads are
considered. Two major conclusions for desktop workloads are drawn: the core is the
largest power consumer and it contains the most variability across workloads. Though
other subsystems, such as memory controller and DIMM, have significant variability
within workloads, only the core demonstrates significant variability in average power
across desktop workloads. Consider Figure 4.5: while average core power varies by as
much as 57 percent, the next most variable subsystem, DIMM, varies by only 17 percent.
Note, this conclusion does not hold for server systems and workloads in which much
larger installations of memory modules cause greater variability in power consumption.
The cause of this core power variation can be attributed to a combination of variable
levels of thread-level parallelism and core-level power adaptations. In the case of 3D, the
workload is able to consistently utilize multiple cores.
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