Merge "docs: Battery performance, networking analysis and optimization" into mnc-docs

page.title=Optimizing Battery Life

page.tags=network,internet

page.tags=battery,network,internet

page.metaDescription=Learn how to optimize your app to reduce battery drain and use power-hungry resources efficiently.

page.article=true

trainingnavtop=true

startpage=true

</div>

<p>For your app to be a good citizen, it should seek to limit its impact on the battery life of its

host device. After this class you will be able to build apps that modify their functionality

and behavior based on the state of the host device.</p>

device. After this class you will be able to build apps that modify their functionality

and behavior based on the state of its device.</p>

<p>By taking steps such as disabling background service updates when you lose connectivity, or

reducing the rate of such updates when the battery level is low, you can ensure that the impact of

your app on battery life is minimized, without compromising the user experience.</p>

<p>By taking steps such as batching network requests, disabling background service updates when you

lose connectivity, or reducing the rate of such updates when the battery level is low, you can

ensure that the impact of your app on battery life is minimized, without compromising the user

experience.</p>

<h2>Lessons</h2>

will want to jump to a lesson or not.-->

<dl>

  <dt><b><a href="{@docRoot}training/performance/battery/network/index.html">Reducing Network Battery

Drain</a></b></dt>

  <dd>Learn how to analyze your app's use of network resources and optimize it to reduce

power consumption.</dd>

  <dt><b><a href="doze-standby.html">Optimizing for Doze and App Standby</a></b></dt>

  <dd>Learn how to test and optimize your app for the power-management features introduced in

  Android 6.0 Marshmallow.</dd>

page.title=Optimizing General Network Use

trainingnavtop=true

@jd:body

<div id="tb-wrapper">

<div id="tb">

<h2>This lesson teaches you to</h2>

<ol>

  <li><a href="#compress-data">Compress Data</a>

  <li><a href="#cache-locally">Cache Files Locally</a></li>

  <li><a href="#pre-fetch">Optimize Pre-Fetch Cache Size</a></li>

</ol>

</div>

</div>

<p>

  In general, reducing the amount of network traffic helps reduce battery drain.

  In addition to the battery-optimization techniques of the previous lessons,

  you should look at these general-purpose techniques and see if you can apply

  them to your app.

</p>

<p>

  This lesson briefly covers techniques that you can use to lower network traffic and

  consequently reduce the battery drain caused by your app.

</p>

<h2 id="compress-data">Compress Data</h2>

<iframe width="448" height="252"

    src="//www.youtube.com/embed/IwxIIUypnTE?autohide=1&showinfo=0"

    frameborder="0" allowfullscreen=""

    style="float: right; margin: 0 0 20px 20px;"></iframe>

<p>

  Reducing the amount of data sent or received over a network connection also

  reduces the duration of the connection, which conserves battery. You can:

</p>

<ul>

  <li>Compress data, using a compression technique such as GZIP compression.</li>

  <li>Use succinct data protocols. While JSON and XML offer human-readability, and

    language-flexibility, they are bandwidth-heavy formats, with

    high serialization costs in the Android platform. Binary serialization formats,

    such as <a href="https://developers.google.com/protocol-buffers/">Protocol Buffers</a> or

    <a href="https://google.github.io/flatbuffers/">FlatBuffers</a> offer a smaller on-the-wire

    packet size, as well as faster encoding and decoding time. If your application transfers a lot

    of serialized data on a regular basis, these formats can yield benefits for decoding time and

    transfer size.

  </li>

</ul>

<h2 id="cache-locally">Cache Files Locally</h2>

<iframe width="448" height="252"

    src="//www.youtube.com/embed/7lxVqqWwTb0?autohide=1&showinfo=0"

    frameborder="0" allowfullscreen=""

    style="float: left; margin: 0 20px 20px 0;"></iframe>

<p>

  Your app can avoid downloading duplicate data by caching. Always cache static resources,

  including on-demand downloads such as full size images, and cache them for as long as reasonably

  possible.

</p>

<p>

  For example, you should consider this approach for a networked app that displays data from

  user-initiated network requests as the primary content on the screen. When the user opens this

  screen the first time, the app should display a splash screen. Subsequent loads should initially

  load with the data that was cached from the last network request. The screen reloads with

  new data once the network request is complete.

</p>

<p>

  To learn about caching, watch the video. To implement caching in your app, see <a href=

  "{@docRoot}training/efficient-downloads/redundant_redundant.html#LocalCache">Cache Files

  Locally</a>.

</p>

<h2 id="pre-fetch">Optimize Pre-Fetch Cache Size</h2>

<p>

  Optimize pre-fetch cache size based on local file system size and current network connectivity.

  You can use the connectivity manager to determine what type of networks (Wi-FI, LTE, HSPAP, EDGE,

  GPRS) are active and modify your pre-fetching routines to minimize battery load.

</p>

<p>

  For more information, see

  <a href="{@docRoot}training/efficient-downloads/connectivity_patterns.html#Bandwidth">Use

  Modifying your Download Patterns Based on the Connectivity Type</a>.

</p>