Android 性能优化（26）＊性能工具之「Batterystats，Battery Historian」Batterystats & Battery Historian Walkthrough

Batterystats & Battery Historian Walkthrough

　　Working with Batterystats & Battery Historian

　　Battery Historian Charts

　　You should also read

• Battery Historian Charts
• Systrace Walkthrough

1.Batterystats

1.1 简介

　　This walkthrough shows the basic usage and workflow for the Batterystats tool and the Battery Historian script.

　　Batterystats collects battery data from your device, and Battery Historian converts that data into an HTML visualization that you can view in your Browser. Batterystats is part of the Android framework, and Battery Historian is open-sourced and available on GitHub at https://github.com/google/battery-historian.

　Batterystats用来收集电池健康数据。它是android 5.0以后内置的一个服务。
　Battery Historian 用来把收集到的数据转换成html，它是个开源项目，请看：https://github.com/google/battery-historian

　　What it's good for:

　本文主题：

• Showing you where and how processes are drawing current from the battery.

  显示当前进程的电量消耗情况。

• Identifying tasks in your app that could be deferred or even removed to improve battery life.

  标识哪些电量消耗可以延迟或删除。 

1.2 要求

　　rerequisites 使用本工具的前提是5.0以上

• A mobile device with Developer Options enabled running Android 5.0 or higher.

1.3 使用步骤

1. Download the open-source Battery Historion Python script from GitHub (https://github.com/google/battery-historian).

   下载 Battery Historion Python

2. Unzip the file to extract the Battery Historian folder. Inside the folder, find the historian.py file and move it to the Desktop or another writable directory.

   解压后，拷贝 scripts/historian.py 到一个有写权限的目录，如~/Android/batterystats

3. Connect your mobile device to your computer.

   连接设备

4. On your computer, open a Terminal window.

   打开命令终端

5. Change to the directory where you've saved historian.py, 
   for example: cd ~/Android/batterystats

   进入到 historian.py 所在目录。
   $cd ~/Android/batterystats

6. Shut down your running adb server. 

   停止adb server
   $adb kill-server

7. Restart adb and check for connected devices. 
   

   查看连接的设备,如下图：注意设备要打开调试模式。
   $adb devices

    
   If you don't see any devices, make sure your phone is connected, and USB Debugging is turned on, and then kill and restart adb.

8. Reset battery data gathering. 

   运行截取电量命令,其中--reset选项清空原有的数据，这样只记录你的应用消耗的电量数据。
   $adb shell dumpsys batterystats --reset

   Resetting erases old battery collection data; otherewise, the output will be huge.

9. Disconnect your device from your computer so that you are only drawing current from the device's battery.

   断开连接，确保你是唯一使用电池的应用。

10. Play with your app for a short time.

    短暂运行你的应用。

11. Reconnect your phone.

    重新连接设备。

12. Make sure your phone is recognized: > adb devices

    确保通过$adb devices能看到你的设备。

13. Dump all battery data. This can take a while: 

    把电量数据输出到一个文本文件。
    $adb shell dumpsys batterystats > ~/Android/batterystats/batterystats.txt

14. Create a HTML version of the data dump for Battery Historian: 

    把上一步生成的文本文件生成html。
    $python historian.py batterystats.txt > batterystats.html

15. Open the batterystats.htm file in your browser.

    用浏览器打开刚生成的html文件。这个html可能需要vpn连网，没有vpn直接断网查看。

16. Continue with Battery Historian Charts.

    开始分析。 

　　前15步的总结

Summary
https://github.com/google/battery-historian
> cd ~/Android/batterystats
> adb kill-server
> adb devices
> adb shell dumpsys batterystats --reset
<disconnect and play with app>...<reconnect>
> adb devices
>adb shell dumpsys batterystats > ~/Android/batterystats/batterystats.txt
> python historian.py batterystats.txt > batterystats.html

2.Battery Historian Charts

• Battery usage categories
• Filtering batterystats output

　　You should also read

• Batterystats & Battery Historian Walkthrough
• Systrace Walkthrough

2.1 简介　

　　The Battery Historian chart graphs power-relevant events over time.

　　Each row shows a colored bar segment when a system component is active and thus drawing current from the battery. The chart does not show how much battery was used by the component, only that the app was active. Charts are organized by category.

　　　　　　　　　　　　　　　　Figure 1. Example of Battery Historian output.

2.2 各字段的含义　

• battery_level: When the battery level was recorded and logged. Reported in percent, where 093 is 93%. Provides an overall measure of how fast the battery is draining.

  电量消耗速度等级，值是百分比，093就是93%

• top: The application running at the top; usually, the application that is visible to the user. If you want to measure battery drain while your app is active, make sure it's the top app. If you want to measure battery drain while your app is in the background, make sure it's not the top app.

  收集电量数据时，系统中处于top的应用，如果你的应用是前台的，请确保它是top的。除非你想知道你的应用在后台时的电量消耗。

• wifi_running: Shows that the Wi-Fi network connection was active.

  wifi连接活跃时间。

• screen: Screen is turned on.

  屏幕点亮时间。

• phone_in_call: Recorded when the phone is in a call.

  通话时间。

• wake_lock: App wakes up, grabs a lock, does small work, then goes back to sleep. This is one of the most important pieces of information. Waking up the phone is expensive, so if you see lots of short bars here, that might be a problem.

  注意，在表格中，它是代＊的，它是最重要的参考。
  通常应用的运行周期是启动，运行一些作业，然后睡觉。启动是最费资源的，如果在这行里出现多个小坚条，说明有问题。

• running: Shows when the CPU is awake. Check whether it is awake and asleep when you expect it to be.

  cpu运行时间。

• wake_reason: The last thing that caused the kernel to wake up. If it's your app, determine whether it was necessary.

  内核最后一次唤醒的原因。如果是由你的应用唤醒，请确定是否必要这么做。

• mobile_radio: Shows when the radio was on. Starting the radio is battery expensive. Many narrow bars close to each other can indicate opportunities for batching and other optimizations.

  无线电开启的时间，开无线电非常耖电。这里出现密集的小坚条，说明有优化空间。

• gps: Indicates when the GPS was on. Make sure this is what you expect.

  gps开启的时间。

• sync: Shows when an app was syncing with a backend. The sync bar also shows which app did the syncing. For users, this can show apps where they might turn syncing off to save battery. Developers should sync as little as possible and only as often as necessary.

  正在后台同步的应用。

　　Note: Not every chart will show every category.

　注意，上面的每行分类只是根据当前开启的功能或服务，应用收集的数据。并不是每次都一样，如wifi没开，就不会有wifi相关的数据，gps没开就没有gps相关数据。

2.3 一些在上述html中未显示信息

　　You can gather additional information from the batterystats.txt file where you saved the output from the batterystats command.

　batterystats.txt 显示的是全部数据。batterystats.html显示的只是它分析时所需的数据。

　　　　　　

　　　　　　　　　　Figure 2.Example of filtered batterystats output.

　　Open the file in a text editor and search for:

• Battery History: A time series of power-relevant events, such as screen, Wi-Fi, and app launch. These are also visible through Battery Historian.

  与电量相关行为的的历史记录。

• Per-PID Stats: How long each process ran.

  每个应用进程运行的时间。

• Statistics since last charge: System-wide statistics, such as cell signal levels and screen brightness. Provides an overall picture of what's happening with the device. This information is especially useful to make sure no external events are affecting your experiment.

  最近一次充电时系统参数的统计，如电池信号等级，屏幕亮度。

• Estimated power use (mAh) by UID and peripheral: This is currently an extremely rough estimate and should not be considered experiment data.

  粗略统计电池的mAh。

• Per-app mobile ms per packet: Radio-awake-time divided by packets sent. An efficient app will transfer all its traffic in batches, so the lower this number the better.

  使用无线电设备传输数据的时间间隔。好的应用会以密集批量方式传输。

• All partial wake locks: All app-held wakelocks, by aggregate duration and count.

  wakelocks的统计。