Affiliations: University of Szeged, Department of Software
Engineering, Árpád tér 2, H-6720 Szeged, Hungary | University of Kaiserslautern, Department of Electrical
Engineering, Erwin-Schrödinger-Straß e, D-67663 Kaiserslautern,
Germany
Abstract: Energy efficiency is key in embedded system design. Understanding
the complex issue of software power consumption in early design phases is of
extreme importance to make the right design decisions. Here, not only the CPU
but also the external memory plays a very important role. Power simulators
offer flexibility and allow a detailed view on the sources of power
consumption. However, many simulators lack accuracy and focus only on the CPU
core without considering the memory subsystem. In this paper, we present XEEMU,
a fast, cycle-accurate simulator, which aims at accurately simulating the power
consumption of an XScale-based system including its memory subsystem. It has
been validated using measurements on real hardware and shows a high accuracy
for runtime, instantaneous power, and total energy consumption estimation. The
average error is as low as 3.0% and 1.6% for runtime and CPU energy consumption
estimation, respectively.
Keywords: XScale, power dissipation, energy consumption, simulation, SDRAM, DVFS