Measurements analysis of the softwarerelated power consumption in microprocessors. Instrumentation and Measurement

In this paper the measurements taken for the development of instruction-level energy models for microprocessors are presented and analyzed. An appropriate measuring environment and a suitable measuring methodology was developed for taking the necessary measurements. The energy of an instruction is defined as a sum of three components which are the pure base energy cost, the inter-instruction cost and the effect of the energy sensitive factors (instruction parameters). These components are characterized for each instruction of the ARM7TDMI embedded processor and their values are analyzed. Using the resulted models estimates of the energy consumption of real software kernels with only up to 6 % error was determined. Last years, low power consumption has been established as the third main design target for digital systems together with performance and area. Consequently, accurate estimators of the power consumption at the system as well as the lower levels of abstraction are necessary. A large number of embedded computing applications are power or energy critical. Early work on processor analysis had focused on performance improvement withou