App power consumption hw5

1. HW 5 App power profiling
資工組
陳顥文
P76034305

2. Requirement
• 上次的作業是請大家對mobile device上的components進行耗電量的測試，接下來希
望大家選定一個APP去進行耗電量分析。此工作請分為兩部分進行:
• 利用APP行為去預估分析其耗電量。
• 實際測試其耗電量。
• 實驗步驟如下:
• 規劃APP使用動作與流程，以重複實驗。
• 建置設計兩種不同的使用環境，包含Android系統的狀態以及是否允許其他Activity或者
services同時進行?
• 分析此兩種使用環境下的耗電量差異為何?
• 比較預估方式與實測的耗電量差距並分析其原因。
• 當手機的耗電量達到低臨界值時，系統該如何因應?
• 將無用的service停掉?
• 將components停掉?
• 強制關閉部分APP?
• 置之不理?....etc

3. Device
• Sony Z Ultra C6833 LTE version with official 4.4.4 ROM
• 2.20GHz Qualcomm Snapdragon 800
• Elpida LPDDR2 RAM
• 6.4” 1080*1920
• Daily use application load and run.

4. General Setting
• Not turn on Airplane mode.
• Not limit CPU.
• Keep Location, Bluetooth, WiFi, Cellular on.
• Allow all background service active.

5. Scenario
• Scenario A
• IN DOOR WIFI (Home)
• OUT DOOR Cellular+GPS Place A (NCKU)
• OUT DOOR Cellular+GPS Place B (Taipei MRT)
• Scenario B
• IN DOOR WIFI (Home)
• OUT DOOR Cellular+GPS Place A (NCKU)
• OUT DOOR Cellular+GPS Place B (Taipei MRT)

6. Scenario
• Scenario C
• OUT DOOR Cellular+GPS Place A (NCKU)

7. Scenario A steps
1. 桌面打開FB點右上角檢視通知 隨便點入檢視任3通知
2. 切換到訊息畫面，找任一人對談話來回各10句，4個貼圖
3. 切換到社團畫面
4. 切換到USER自己的畫面，並點及相片，選擇有你在內的相片任
一張放大檢視
5. 退出到自己的畫面，發一則文字近況，並且標地標
6. 結束
• 估計5分鐘內完成

8. IN-DOOR WIFI CONNECT Scenario
A HOME

9. IN-DOOR WIFI CONNECT Scenario A HOME
• FB won’t using in physic GPS to locate real location.(guess due to WIFI
location provide enough precision).
• Min lid, disable auto brightness.
• Simulate normal using FB at home.

10. IN-DOOR WIFI CONNECT Scenario A Estimate
HOME
假設歷時5分鐘
平均耗電流
(mA)
執行時間
佔總時間比例
平均值行
時間耗電量
CPU FULL LOAD -1000 10% -100
CPU 3C LOAD -800 20% -160
CPU 2C LOAD -600 50% -300
CPU 1C LOAD -400 20% -80
CPU TOTAL AVG -640
比例
WIFI ACTIVE 包含 MIN MONITOR -500 50% -250
預估總時間(秒) 300
預估平均消耗電流 -890mA

11. IN-DOOR WIFI CONNECT Scenario A Real
HOME
實際狀況 實際時間
第一次測試平均 -659.429 5 min 12 sec
第二次測試平均 -739.090 4 min 46 sec
第三次測試平均 -708.973 4 min 32 sec
實際平均 -702.497

12. IN-DOOR WIFI CONNECT Scenario A HOME
Guess reason
• Estimate error rate: 26.7%
• Cause estimating CPU usage percent too high.
• CPU hardly getting full load(2.15Ghz).
• Most time CPU usage around 50~60%.

13. OUT-DOOR CELLULAR CONNECT
Scenario A NCKU

14. OUT-DOOR CELLULAR CONNECT Scenario A
NCKU
• FB will seen not using GPS in 打卡 & Message sending.
• Using cellular network with variable signal strength condition.
• 58%, -98dBm @ NCKU Success middle area.
• Max lid, disable auto brightness.

15. OUT-DOOR CELLULAR CONNECT Scenario A
NCKU Estimate
預估總時間(秒) 300
預估平均消耗電流 -1130mA
假設歷時5分鐘
平均耗電流
(mA)
執行時間佔
總時間比例
平均執行時間耗電量
CPU FULL LOAD -1000 5% -50
CPU 3C LOAD -800 10% -80
CPU 2C LOAD -600 30% -180
CPU 1C LOAD -400 55% -220
CPU TOTAL AVG 100% -530
MAX MONITOR LID -400 100% -400
Cellular -500 40% -200

16. OUT-DOOR CELLULAR CONNECT Scenario A
NCKU Real
實際狀況 實際時間
第一次測試平均 -1147.284544 3 min 55 sec
第二次測試平均 -1204.964724 3 min 46 sec
第三次測試平均 -1163.484078 3 min 49 sec
實際平均 -1171.911115

17. OUT-DOOR CELLULAR CONNECT Scenario A
NCKU Guess reason
• Estimate error rate: 3.576%
• More accurate estimate CPU usage.

18. OUT-DOOR CELLULAR CONNECT
Scenario A Taipei Q-Station

19. OUT-DOOR CELLULAR CONNECT Scenario A
Taipei Q-Station
• FB will using GPS in 打卡 & Message sending.
• Using cellular network with variable signal strength condition.
• 86%, -79dBm @ Taipei Q-Station 2F.
• Max lid, disable auto brightness.

20. OUT-DOOR CELLULAR CONNECT Scenario A
Taipei Q-Station Estimate
預估總時間(秒) 300
預估平均消耗電流 -1180mA
假設歷時5分鐘
平均耗電流
(mA)
執行時間佔
總時間比例
平均執行時間耗電量
CPU FULL LOAD -1000 5% -50
CPU 3C LOAD -800 10% -80
CPU 2C LOAD -600 30% -180
CPU 1C LOAD -400 55% -220
CPU TOTAL AVG 100% -530
GPS -500 10% -50
MAX MONITOR LID -400 100% -400
Cellular -500 40% -200

21. OUT-DOOR CELLULAR CONNECT Scenario A
Taipei Q-Station Real
實際狀況 實際時間
第一次測試平均 -1256.658157 3 min 28 sec
第二次測試平均 -1266.342114 3 min 41 sec
第三次測試平均 -1302.819672 3 min 18 sec
實際平均 -1275.273314

22. OUT-DOOR CELLULAR CONNECT Scenario A
Taipei Q-Station Guess reason
• Estimate error rate: 7.471%
• CPU average usage increase.
• More GPS consume.
• RF IC need more compute to anti-interference??

23. Scenario B steps
1. 打開FB
2. 點選已經PO在自己FB塗鴉牆上的1分鐘影片，音量中等，接耳機
3. 打卡並上傳3張照片。
4. 分享3張照片給一位好友。
5. 聊天10句，4則訊息。
6. 結束
• 預計5分鐘完成

24. IN-DOOR WIFI CONNECT Scenario
B HOME

25. IN-DOOR WIFI CONNECT Scenario B
• FB won’t using in physic GPS to locate real location.(guess due to WIFI
location provide enough precision).
• Min lid, disable auto brightness.
• Simulate entertainment using FB at home.

26. IN-DOOR WIFI CONNECT Scenario B Estimate
HOME
假設歷時5分鐘
平均耗電流
(mA)
執行時間
佔總時間比例
平均值行
時間耗電量
CPU FULL LOAD -1000 0% 0
CPU 3C LOAD -800 10% -80
CPU 2C LOAD -600 60% -360
CPU 1C LOAD -400 30% -120
CPU TOTAL AVG -560
比例
WIFI ACTIVE 包含 MIN MONITOR -500 50% -250
預估總時間(秒) 300
預估平均消耗電流 -890mA

27. IN-DOOR WIFI CONNECT Scenario B Real
HOME
實際狀況 實際時間
第一次測試平均 -774.1553939 3 min 16 sec
第二次測試平均 -737.5024394 3 min 15 sec
第三次測試平均 -754.0005818 2 min 44 sec
實際平均 -755.2194717

28. IN-DOOR WIFI CONNECT Scenario B HOME
Guess reason
• Estimate error rate: 7.2536%
• More accurate estimate CPU usage.

29. OUT-DOOR CELLULAR CONNECT
Scenario B NCKU

30. OUT-DOOR CELLULAR CONNECT Scenario B
NCKU
• FB will seen not using GPS in 打卡 & Message sending.
• Using cellular network with variable signal strength condition.
• 58%, -98dBm @ NCKU Success middle area.
• Max lid, disable auto brightness.
• Simulate entertainment using FB at outdoor.

31. OUT-DOOR CELLULAR CONNECT Scenario B
NCKU Estimate
預估總時間(秒) 300
預估平均消耗電流 -1100mA
假設歷時5分鐘
平均耗電流
(mA)
執行時間佔
總時間比例
平均執行時間耗電量
CPU FULL LOAD -1000 0% 0
CPU 3C LOAD -800 10% -80
CPU 2C LOAD -600 30% -180
CPU 1C LOAD -400 60% -240
CPU TOTAL AVG 100% -500
MAX MONITOR LID -400 100% -400
Cellular -500 40% -200

32. OUT-DOOR CELLULAR CONNECT Scenario B
NCKU Real
實際狀況 實際時間
第一次測試平均 -1159.806061 4 min 53 sec
第二次測試平均 -1114.94688 3 min 43 sec
第三次測試平均 -1155.352031 4 min 52 sec
實際平均 -1143.368324

33. OUT-DOOR CELLULAR CONNECT Scenario B
NCKU Guess reason
• Estimate error rate: 3.793%
• More accurate estimate CPU usage.
• Guess there have hardware video decode.

34. OUT-DOOR CELLULAR CONNECT
Scenario B Taipei Q-Station

35. OUT-DOOR CELLULAR CONNECT Scenario B
Taipei Q-Station
• FB will using GPS in 打卡 & Message sending.
• Using cellular network with variable signal strength condition.
• 58%, -98dBm @ NCKU Success middle area.
• Max lid, disable auto brightness.
• Simulate entertainment using FB at general public area.

36. OUT-DOOR CELLULAR CONNECT Scenario B
Taipei Q-Station Estimate
預估總時間(秒) 300
預估平均消耗電流 -1100mA
假設歷時5分鐘
平均耗電流
(mA)
執行時間佔
總時間比例
平均執行時間耗電量
CPU FULL LOAD -1000 0% 0
CPU 3C LOAD -800 10% -80
CPU 2C LOAD -600 30% -180
CPU 1C LOAD -400 60% -240
CPU TOTAL AVG 100% -500
MAX MONITOR LID -400 100% -400
Cellular -500 40% -200

37. OUT-DOOR CELLULAR CONNECT Scenario B
Taipei Q-Station Real
實際狀況 實際時間
第一次測試平均 -1229.883714 4 min 18 sec
第二次測試平均 -1212.0658 3 min 53 sec
第三次測試平均 -1289.8889 3 min 36 sec
實際平均 -1243.946138

38. OUT-DOOR CELLULAR CONNECT Scenario B
Taipei Q-Station Guess reason
• Estimate error rate: 11.572%
• CPU average usage increase.
• RF IC need more compute to anti-interference??

39. Scenario C steps
1. 打開FB
2. 點選已經PO在自己FB塗鴉牆上的1分鐘20秒影片，音量中等，接耳
機，分別切換測試一般畫質/HD畫質。
3. 結束
• 預計2分鐘完成

40. OUT-DOOR CELLULAR CONNECT
Scenario C NCKU

41. OUT-DOOR CELLULAR CONNECT Scenario C
NCKU
• See different consumption in different video quality.(Real Data only)
• Low Quality:
• AVG Current(mA): -870.4692
• CPU Usage: 49.84375%
• High Quality:
• AVG Current(mA): -943.8936944
• CPU Usage: 52.40625%
• Cause by more network traffic or video decode?

42. -1400
-1200
-1000
-800
-600
-400
-200
0
SCNARIO A
INDOOR
SCNARIO A
NCKU
SCNARIO A
TAIPEI
SCNARIO B
INDOOR
SCNARIO B
NCKU
SCNARIO B
TAIPEI
SCNARIO C
NCKU LQ
SCNARIO C
NCKU HQ
-702.497682
-1171.911115
-1275.273314
-755.2194717
-1143.368324
-1243.946138
-870.4692
-943.8936944
-890
-1130
-1180
-810
-1100
-1100
Real comsuption
Real Estimate

43. -15%
-10%
-5%
0%
5%
10%
15%
20%
25%
30%
SCNARIO A
INDOOR
SCNARIO A
NCKU
SCNARIO A
TAIPEI
SCNARIO B
INDOOR
SCNARIO B
NCKU
SCNARIO B
TAIPEI
27%
-4% -7%
7%
-4%
-12%
Error Rate

44. Adopt a measure when low battery capacity
• Disable non-system service, stay only system necessary service.
• Disable GPU 3D rendering in Desktop manager.
• Disable animation transition effect.
• Disable GPS, Mobile Data, WIFI, BT, NFC, but keep cellular on.
• Disable G-Sensor(for Monitor rotator)
• Disable Light-Sensor(for Auto brightness adjust)
• Mini Monitor lid.
• Limit CPU Speed, limit active core.

45. Graceful implement battery saver method
1. 到達臨界前(例如25%)
2. 開始記錄開過的前景ACTIVITY
3. 到達20%時，再比對一下誰的執行時間最長
4. 判斷執行App名稱->預先已經有DB（節省其他能源消耗）
5. DB告訴系統節電措施，目標APP最少需要什麼硬體（例如地圖
要GPS, 網路）
6. 關閉目標APP需要硬體以外的硬體。

46. 從電量25%開始，紀錄每個APP使用時間T,以及每個硬體的消耗電量
E(ex. CPU使用率)
決定每個硬體的最高電量使用Esave
參考某APP過去五分鐘
加權E'(app) = (5*E1+4*E2+3*E3+2*E4+E5) / 15
加權T'(app) = (5*T1+4*T2+3*T3+2*T4+T5) / 15
Tsum = sum(T')
得出某APP的使用比重 X(app) = T'(app)/Tsum
又C*( sum(E'(app)*X(app) )) = Esave(CPU)
計算常數C
最後限制某APP的CPU最高電量使用為E'(app)*X(app)*C

47. About this slide
• Author: Nathaniel Chen
• Email: ar801112usase@hotmail.com
• Last update time:2015/04/23 0043 v1.1