適用於嵌入式產品之程序及元件耗能評估工具

Abstract

近年來，減少耗能已成為嵌入式系統的一項重要議題，為了延長系統的使用時間，我們需要更有效率地去使用每一份能源。在一般的消費性 3C 產品裡， 使用者普遍只能知道電池的剩餘電量，然而這項資訊並無法提供使用者足夠的線索，去找出背後耗電的真正原因。因此，研究人員意識到，節能的需求需要對系統上的耗電情形有深一步的瞭解與分析。過去有許多研究在這領域提出各自的方法與工具去協助使用者評估耗能，然而由於嵌入式產品上的限制，使得他們的方法難以運用於嵌入式產品。為此，我們提出一套工具，eTop，僅需透過電池的剩餘電量這項資訊，便可帶領使用者們深入瞭解系統上每個程序在每個系統元件上的耗電情況。我們的工具實做於 Linux 作業系統之上，而我們也在 Creator PreSOCes 開發板上設計了幾項實驗來測試eTop的效能與準確度。實驗結果顯示元件層級的耗電分析的誤差約在 8% 以下，而程序層級的耗電分析的誤差約在 6.68%。

Efficient energy utilization has long been a critical issue for battery-powered devices. For most 3C products, although the information about the remaining battery time can be found easily, no explanation is provided regarding where energy is excessively consumed. Therefore, detailed energy profiling is the fundamental requirement for helping users resolving the energy utilization issue. Prior research proposed their own approaches which are, however, not readily applicable to embedded end-products. Hence, we propose an energy profiler, eTop, to address energy use in embedded end-products. Implemented on Linux OS, eTop estimates energy consumption of different processes on several major system components, such as CPU, SDRAM, WIFI, and LCD. In order to verify the experimental results, we choose the Creator PreSOCes development board and conduct several experiments on it. The results demonstrate that the average error of component-level energy profiling is below 8%, and the average error of process-level energy profiling is around 6.68%.