page.title=Memory Monitor Walkthrough
meta.tags="android, performance, profiling, tools, memory, memoryleaks, garbagecollection, memorymonitor"
page.tags="android", "performance", "profiling", "tools", "memory", "memoryleaks", "garbagecollection", "memorymonitor"
page.metaDescription=Graph memory usage and garbage collection events for your app in real-time.
page.image=tools/performance/thumbnails/tools_memory_monitor.png
page.article=true

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<h2>In this document</h2>
<ul>
  <li><a href="#WhatYouNeed">Prerequisites</a></li>
  <li><a href="#WorkingWithMemoryMonitor">Working with Memory Monitor</a></li>
</ul>

<h2>You should also read</h2>
<ul>
  <li><a href="{@docRoot}tools/performance/heap-viewer/index.html">
    Heap Viewer Walkthrough</a></li>
  <li><a href="{@docRoot}tools/performance/allocation-tracker/index.html">
    Allocation Tracker Walkthrough</a></li>
  <li><a href="{@docRoot}tools/performance/comparison.html">
    Comparison: Memory Monitor, Heap Viewer, Allocation Tracker</a>
  <li><a href="{@docRoot}tools/performance/traceview/index.html">
    Traceview Walkthrough</a></li>
</ul>

</div>


  <p>This walkthrough shows the basic usage and workflow for the Memory Monitor tool in Android
  Studio. Memory Monitor reports in real-time how your app allocates memory.</p>

  <p>What it's good for:</p>

  <ul>
    <li>Showing available and used memory in a graph, and garbage collection events over time.</li>

    <li>Quickly testing whether app slowness might be related
    to excessive garbage collection events.</li>

    <li>Quickly testing whether app crashes may be related to running out of
    memory.</li>
  </ul>

  <h2 id="WhatYouNeed">Prerequisites</h2>

  <ul>
    <li>A mobile device with <a href=
    "http://developer.android.com/tools/device.html#developer-device-options">Developer Options</a>
    enabled.</li>

    <li>An Application with USB Debugging enabled. Use your own, or the <a href=
    "https://github.com/udacity/Sunshine-Version-2">Sunshine</a> sample app from the <a href=
    "https://www.udacity.com/course/ud853">Android Fundamentals Udacity course</a>.</li>
  </ul>

  <h2 id="WorkingWithMemoryMonitor">Working with Memory Monitor</h2>

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    <div class="figure" style="">
  <img src="{@docRoot}images/tools/performance/memory-monitor/gettingstarted_image001.png"
         alt=""
         width="300px" />
      <p class="img-caption">
        <strong>Figure 1. </strong>Starting Memory Monitor.
      </p>
    </div>

    <li>If you're using a mobile device, connect it to your computer.</li>

    <li>Open your application in Android Studio, build the source,
      and run it on your device or emulator.</li>

    <li>In Android Studio, choose <strong> Tools &gt; Android &gt; Memory Monitor</strong>. You
      can also click the <em>Android</em> tab in the lower-left corner of the application
      window to launch the Android runtime window. The CPU and Memory Monitor views appear.</li>
 
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  <img src="{@docRoot}images/tools/performance/memory-monitor/gettingstarted_image003.png"
         alt=""
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      <p class="img-caption">
        <strong>Figure 1. </strong>Allocated and free memory in Memory Monitor.
      </p>
    </div>

    <li>Once Memory Monitor starts tracking your device, a stacked graph appears,
      tracking memory usage over time.

      <p>Dark blue: Amount of memory that your app
      is currently using.</p>

      <p>Light blue: Available, unallocated memory.</p>
    </li>

    <li>Over time, this graph updates, showing changes in memory usage.</li>

    <li>As your app allocates and frees memory, the allocated amount shown in the
      graph changes.</li>

    <li>When you see the allocated memory drop by a large amount, a garbage
      collection (GC) event has occurred.</li>

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</div></li>

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    <div class="figure" style="">
  <img src="{@docRoot}images/tools/performance/memory-monitor/gettingstarted_image005.png"
         alt=""
         width="400px" />
      <p class="img-caption">
        <strong>Figure 2. </strong>Forcing a GC (Garbage Collection) event.
      </p>
    </div>

    <li>You can force a garbage collection event by clicking on the garbage truck
      icon
<img src="{@docRoot}images/tools/performance/memory-monitor/gettingstarted_image004.png">.
    </li>

 </ol>
</div></li>
</ul>