Massive data centers housing thousands of computing nodes
have become commonplace in enterprise computing, and the
power consumption of such data centers is growing at an
unprecedented rate. Adding to the problem is the inability
of the servers to exhibit energy proportionality, i.e., provide
energy-ecient execution under all levels of utilization,
which diminishes the overall energy eciency of the data
center. It is imperative that we realize eective strategies
to control the power consumption of the server and improve
the energy eciency of data centers. With the advent of
Intel Sandy Bridge processors, we have the ability to specify
a limit on power consumption during runtime, which creates
opportunities to design new power-management techniques
for enterprise workloads and make the systems that they run
on more energy-proportional.
In this paper, we investigate whether it is possible to achieve
energy proportionality for an enterprise-class server workload,
namely SPECpower ssj2008 benchmark, by using Intel's
Running Average Power Limit (RAPL) interfaces. First,
we analyze the power consumption and characterize the instantaneous
power prole of the SPECpower benchmark at
a subsystem-level using the on-chip energy meters exposed
via the RAPL interfaces. We then analyze the impact of
RAPL power limiting on the performance, per-transaction
response time, power consumption, and energy eciency of
the benchmark under dierent load levels. Our observations
and results shed light on the ecacy of the RAPL interfaces
and provide guidance for designing power-management techniques
for enterprise-class workloads
