Android Method Trace Generation and Analysis

date

Oct 11, 2017

slug

android-method-trace-generation-analysis

status

Published

Generating Trace Files

There are two main ways to generate trace files as mentioned in the official documentation.

Code

The first method involves adding code to your project:

This will generate the trace file.

ddmlib

The second method involves using ddms/Android Monitor to manually generate the trace file. ddms relies on a library called ddmlib, which can be found in the Android SDK at tools/lib/ddmlib-*.jar.

There are not many articles available about ddmlib, but you can refer to the following resources: Hidden Boss - Getting Started with ddmlib and Using adb with ddmlib, Building Framework Libraries.

Command-line Tool

While exploring the source code, I encountered numerous challenges and wrote a command-line tool called AndroidMethodTraceRunner.

To use it, run the following command: $ java -jar mtr.jar -p com.your.package -o output.trace -t 10 to trace for 10 seconds. Please note that it requires Java 8 to run.

There are two main issues to be aware of:

AndroidDebugBridge.init(true) - If set to false, the client cannot be accessed.

You must close ddms and the Studio monitor/profiler, otherwise, they will preempt the client and cause a connection failure.

Here are a few key concepts related to ddmlib:

Bridge - adb

Device - the connected device

Client - the application

The main code snippet is as follows:

Android Studio

However, Android Studio 3.0 does not use ddmlib.

The general call stack is as follows:

Trace Parsing/Reading

GUI

ddms or Android Studio 2.0/IntelliJ IDEA can directly open trace files, but they are not as user-friendly as the profiler in Android Studio 3.0.

Command Line Tool

Based on the above analysis I wrote a command line tool based on ddmlib to run Android Method Trace on the fly.

https://github.com/likaci/AndroidMethodTraceRunner