Commit 8ca4e169221528ce22a3649643223b841677ba1d

Authored by Geoffrey Challen
1 parent fd01472c

Done.

.ispell_english 0 → 100644
  1 +Android
  2 +Android's
  3 +app
  4 +app's
  5 +apps
  6 +AudioFlinger
  7 +clickable
  8 +ESPN
  9 +Facebook
  10 +foregrounded
  11 +IRB
  12 +kbps
  13 +OTA
  14 +overvalue
  15 +overweighting
  16 +pedometer
  17 +pedometers
  18 +realtime
  19 +Skype
  20 +smartphone
  21 +smartphones
  22 +Snapchat
  23 +Sportscenter
  24 +SurfaceFlinger
  25 +testbed
  26 +touchscreen
  27 +UI
  28 +undervalue
  29 +uninstall
  30 +WhatsApp
  31 +Yahoo
  32 +YouTube
old/utility.tex deleted
1 -\section{Computing Energy Efficiency}  
2 -\label{sec-utility}  
3 -  
4 -Based on the results from the previous section, we can formulate design  
5 -requirements for an energy efficiency metric to apply to smartphone apps.  
6 -First, it must scale with usage, respecting the differences in baseline  
7 -consumption between users identified in Section~\ref{subsec-uservariation}  
8 -and the temporal variation of apps identified in  
9 -Section~\ref{subsec-timevariation}. Second, it must try to avoid targeting  
10 -top apps, even if they tend to consume a great deal of energy as described in  
11 -Section~\ref{subsec-consumption}, as these may not be apps that users are  
12 -willing to uninstall. Finally, we use the analysis of background energy  
13 -consumption in Section~\ref{subsec-background} as a hint about where to  
14 -start, given that background energy consumption should match foreground usage  
15 -in most cases.  
16 -  
17 -In the section we walk through several ways of characterizing app energy  
18 -consumption: via the total amount, by consumption rate, and scaled against  
19 -foreground energy consumption and a new content-delivery metric we design  
20 -that incorporates use of both the display and the audio device. In each case  
21 -we examine the app consumption data generated by our usage monitoring study  
22 -and use each metric to shed light on app energy consumption.  
23 -  
24 -\subsection{Total Consumption}  
25 -  
26 -\input{./figures/tables/tableTOTAL.tex}  
27 -  
28 -Clearly, ranking apps by total energy consumption over the entire study says  
29 -much more about app popularity than it does about anything else.  
30 -Table~\ref{table-total} shows the top and bottom energy-consuming apps over  
31 -the entire study. As expected, popular apps such as the Android Browser,  
32 -Facebook, and the Android Phone compunent consume the most energy, while the  
33 -list of low consumers is dominated by apps with few installs. This table does  
34 -serve, however, to identify the popular apps in use by \PhoneLab{}  
35 -participants.  
36 -  
37 -\subsection{Consumption Rate}  
38 -  
39 -\input{./figures/tables/tableRATE.tex}  
40 -  
41 -Computing the rate at which apps consume energy by scaling their total energy  
42 -usage against the total time they were running, either in the background or  
43 -foreground, reveals more information, as shown in Table~\ref{table-rate}, The  
44 -results identify Facebook Messenger, Google+, and the Super-Bright LED  
45 -Flashlight as apps that rapidly-consume energy, while the Bank of America and  
46 -Weather Channel apps consume energy slowly. Differences between apps in  
47 -similar categories may begin to identify apps with problematic energy  
48 -consumption, such as contrasting the high energy usage of Facebook Messenger  
49 -with the low usage of WhatsApp, Twitter, Android Messaging, and even Skype.  
50 -  
51 -\subsection{Foreground Energy Efficiency}  
52 -  
53 -\input{./figures/tables/tableFOREGROUND.tex}  
54 -  
55 -Consumption rate alone, however, is insufficient to answer important  
56 -questions about how efficient smartphone apps are. Pandora, for example, may  
57 -consume a great deal of energy either because it is poorly written, or  
58 -because it is delivering a great deal of content. Given the observations  
59 -about background usage presented earlier, we were interested in using an apps  
60 -foreground time as a utility metric to compute energy efficiency. In this  
61 -conceptual framework, smartphone apps deliver utility through screen time  
62 -with users, and should consume energy in proportion to the amount of time  
63 -users spend actively interacting with them.  
64 -  
65 -\subsection{Content Energy Efficiency}  
66 -  
67 -\input{./figures/tables/tableCONTENT.tex}  
68 -  
69 -\subsection{Discussion}  
related.tex deleted
1 -\section{Related Work}  
2 -\label{sec-related}  
3 -One of the main activities on these mobile devices is \textbf{content  
4 -consumption}. A large number of applications for mobile devices are  
5 -content-delivery applications such as browsers, e-book readers, video players,  
6 -audio players, and photo viewers. Surveys have shown that consuming mobile  
7 -content such as video, books, news, etc. is the most popular activity among  
8 -mobile device users~\cite{mobile-content1, mobile-content2}.  
9 -  
10 -But high app usage will often translate to high energy consumption and lack of longevity  
11 -in battery life is reported to be the least satisfying aspect of smartphone ~\cite{battery-complaint1}.  
12 -Previous work on component-based power modelling~\cite{dong2011, zhang2010,  
13 -jung2012} has mapped energy consumption to system-components like cpu, wifi chip, screen etc.  
14 -On the other hand, efforts like Eprof~\cite{pathak2011,pathak2012}, AppScope~\cite{yoon} traces system calls and monitors kernel activities to answer how much energy is consumed in an application level.  
15 -There has also being an impressive body of work to provide accurate energy measurement techniques  
16 -like by using either external hardware~\cite{carroll,  
17 -cignetti} or device-provided, built-in mechanisms such as smart  
18 -battery interfaces and voltage information~\cite{mansdi, vedge-nsdi13}.  
19 -But there has been no work as per our knowledge about identifying how much energy is consumed in providing  
20 -utility to the user. There exists a gap in our understanding what part of energy consumption by an app is  
21 -necessary to provide useful content to the user and what part of it is lost in inefficiency.