- Connect your mobile device to your computer.
- Open your application in Android Studio, build the source, and run it on your device.
- Start the Android Device Monitor from Android Studio: Tools -> Android -> Android Device Monitor.
Figure 1. Steps for starting Android Device Monitor.
- Make sure your device
and the package for your application are showing in the Devices (DDMS mode) or
Windows (Hierarchy Viewer mode) tab.
If necessary choose Window > Reset Perspective to get back to the default pane arrangement.
- Click the DDMS button, because Traceview is one of the DDMS tools.
- Select the app you want to profile.
Figure 2. Steps for starting Traceview.
- Click the Start method profiling
button.
Figure 3. Starting profiling.
- In the Profiling Options popup:
- Choose Sample based profiling
- Keep the default sampling rate of 1000 microseconds.
- Click OK.
Figure 4. Choosing profiling options.
- Interact with your application. If you are aware of performance issues that your users experience, perform those actions.
- Click the Stop method profiling
button. - Wait for the trace to load. This may take a few seconds if you recorded for a long time.
Figure 5. Stopping profiling.
- Traceview has two panels: Timeline pane and Profile pane, which are described below.
- Use the Find box at the bottom to filter your profile results. For example, if you are interested in finding the running time for a function, you can search for it, and the tool will highlight it in the timeline.
Figure 6. Traceview output panes.
- The Timeline pane visualizes how your code executes over time.
- Each row shows a thread.
- Each bar on the timeline is a method executing.
- Each color is for a different method; every time a method executes, you see a the same color bar.
- The width of its bar indicates how long the method takes to execute.
- When you are zoomed out, a bar indicates when a method is executing.
Figure 7. Annotated timeline panel.
- Zoom into the graph, and the bar for each method expands into a colored U-shape, where the left side of the U indicates the start, and the right side the end of the method's execution.
Figure 8. Segment for method on the timeline.
- The Profiling pane shows a list of methods.
- Select a method to see who called it (Parent) and who it's calling (Children).
- The selected method is also highlighted in the Timeline pane.
- The columns show exclusive and inclusive CPU and real times, percentages, ratios, and how often a method was called.
- The exclusive time is the time spent just in the method itself, which can help you find issues within that specific method.
- The inclusive time is for the method and all methods it calls, which can help you find problems with your call tree.
- The Calls+Rec column shows how many times a method was called recursively, which can help you track down performance issues.
Figure 9. Traceview Profiling pane with callstack.