FAKULTÄT FÜR INFORMATIK DER TECHNISCHEN UNIVERSITÄT MÜNCHEN Bachelor Thesis in Information Systems Power demand recording of running mobile applications exemplified by applications for the Android operating system Julia Kindelsberger FAKULTÄT FÜR INFORMATIK DER TECHNISCHEN UNIVERSITÄT MÜNCHEN Bachelor Thesis in Information Systems Power demand recording of running mobile applications exemplified by applications for the Android operating system Aufzeichnung des Energiebedarfs von laufenden mobilen Applikationen am Beispiel von Applikationen für das Android Betriebssystem Author: Julia Kindelsberger Supervisor: Prof. Dr. Helmut Krcmar Advisor: Felix Willnecker, M.Sc. Submission Date: December 15th 2014 I confirm that this bachelor's thesis is my own work and I have documented all sources and material used. Garching bei München, December 15th 2014 _______________________________ Julia Kindelsberger Abstract Knowing the power demand of mobile applications is becoming a key area of interest for both end-users and developers due to the limited battery lifetime of mobile devices. The measurement of the power demand of the hardware components on which the application is running is required in order to understand the power demand of mobile applications. The different power demand performance of various mobile devices and hardware components cause difficulties in measuring the power demand on this granularity. Previous work has shown that differences occur in power demands of applications with similar functionality, and has presented several tools for power demand measurement. These tools often use additional hardware for the measurements, require complicated modifications of the operating system, or cannot provide the required granularity. Therefore, none of these tools provide a simple way for developers to identify the reasons for high power demand, on a hardware component and method level, for their apps. This thesis reviews the existing approaches that measure, record and analyze the power demand of applications, by conducting a literature review and comparing the tools according to defined characteristics, such as target apps, granularity, monitored resources, export of data and needed modifications and restrictions. Based on determined requirements from the review, an Android- based prototype is presented. This prototype records the power demand of the specified hardware components and methods over a longer period, shows real-time information and provides an Excel export for detailed analysis. The prototype is implemented for the recently presented Android operating system version 5.0, which provides new APIs for battery statistics and power demand information. To evaluate the prototype the power demand of three Android fitness apps have been compared (RunnerUp, MyTracks, Runtastic) and differences up to 21.84% were discovered between the apps with similar functionality. Detailed reports detected the reasons for the differences in mobile data usage by up to 405.07%, cell standby up to 144.92 % and CPU up to 7.14%. In addition to the identification of the power consuming hardware components the power demand is determined on a method-level to give developers a point of reference on how to reduce the overall power demand of their applications. Keywords: Power measurements, energy measurements, power demand, energy consumption, mobile application, Android 5.0, Android traceview, energy savings, energy benchmarking, greenness of mobile apps, green IT III Table of contents List of figures ............................................................................................................................... VI List of tables ................................................................................................................................ VII List of abbreviations ................................................................................................................. VIII 1 Introduction .............................................................................................................................. 1 1.1 Motivation ........................................................................................................................ 1 1.2 Objectives ......................................................................................................................... 1 1.3 Related work .................................................................................................................... 2 1.4 Research questions and methodology .............................................................................. 3 1.5 Thesis structure ................................................................................................................ 5 2 Battery-related characterization ............................................................................................. 6 2.1 Characteristics of rechargeable batteries .......................................................................... 6 2.2 Energy consumption and power demand ......................................................................... 7 2.3 Power components ........................................................................................................... 8 3 Approaches for measuring and recording power demand of applications ....................... 11 3.1 Application performance management software ............................................................ 11 3.1.1 Compuware dynaTrace .............................................................................................. 11 3.1.2 Compuware mobile application monitoring ............................................................... 12 3.1.3 AppDynamics ............................................................................................................. 13 3.1.4 New Relic ................................................................................................................... 13 3.1.5 Riverbed Technology ................................................................................................. 14 3.2 Mobile application measurement software .................................................................... 14 3.2.1 AppScope ................................................................................................................... 14 3.2.2 Power Tutor ................................................................................................................ 15 3.2.3 PowerProf ................................................................................................................... 15 3.2.4 Eprof ........................................................................................................................... 15 3.2.5 PowerScope ................................................................................................................ 16 3.2.6 Trepn .......................................................................................................................... 16 3.2.7 Little eye labs ............................................................................................................. 16 3.2.8 Android power profiles .............................................................................................. 17 3.2.9 Android 5.0 developer preview .................................................................................. 18 3.3 Evaluation of the different approaches ........................................................................... 19 4 Approaches for tracing runtime statistics of applications .................................................. 24 4.1 Traceview ....................................................................................................................... 24 4.2 Jstack .............................................................................................................................. 25 4.3 Systrace .......................................................................................................................... 26 4.4 atrace .............................................................................................................................. 27 4.5 Evaluation of the different approaches ........................................................................... 28 IV 5 Prototype implementation ..................................................................................................... 31 5.1 Requirements of the prototype ....................................................................................... 31 5.2 Flowchart of the prototype ............................................................................................. 33 5.3 Architecture of the prototype ......................................................................................... 34 5.3.1 PowerComponentsReader .......................................................................................... 34 5.3.2 TraceviewReader ........................................................................................................ 35 5.3.3 PowerDistributor ........................................................................................................ 35 5.3.4 Exporter ...................................................................................................................... 35 5.3.5 GraphOverlay ............................................................................................................. 35 5.4 Class diagram of the prototype ......................................................................................