How to automate the DDMS snapshot mechanism?

Question

Does Android DDMS provide APIs ? I need to automate the snapshot mechanism for the native heap. Or is there any post processing tool for analysis DDMS native heap snapshots.

Answer 1

I assume by snapshot you mean a heap dump.

From your app code you can call Debug.dumpHprofData() to dump the data.

From a script you can call

adb shell am dumpheap <process> <file>

where <process> is e.g. your process id or name, and <file> is the dump file name. After that you can adb pull the dump to your computer.

To analyze the heap dumps you can use e.g. jhat or MAT. Before that you need to run hprof-conv (included in Android SDK) on the dump to convert it from Dalvik format to standard Java format.

Further reading: Memory Analysis for Android Applications

Answer 2

@laalto's answer is not quite correct

From a shell you can do the following to get a heap dump for the application using adb.

Note: Replace 19000 with the process ID of your running application. The filepath must be a filepath which your application has write access to on the Android device.

Create a heap dump:
adb shell am dumpheap 19000 /sdcard/Documents/android.hprof
Pull the file to your machine:
adb pull /sdcard/Documents/android.hprof
Convert to a hprof file readable by an analyzer:
hprof-conv android.hprof mat.hprof

Tips: Get process ID of your application:

adb shell ps | grep com.sample.application | cut -c10-15

Get process ID and dump heap:

adb shell am dumpheap `adb shell ps | grep com.sample.application | cut -c10-15` /sdcard/Documents/android.hprof

Answer 3

The DDMS provides a UI for the ADB. You can use ADB commands directly and process the output. The ADB documentation can be found here: http://developer.android.com/tools/help/adb.html

Answer 4

I wrote small script, maybe you would find it useful

heap_dump_location='/data/local/tmp/tmp.hprof'

dump_heap() {
  adb shell rm $heap_dump_location
  pid=`adb shell ps | grep 'com.example.packagename' | grep -v 'packagename\.' | cut -c10-15`
  adb shell am dumpheap $pid $heap_dump_location
  echo "Heap dump started, we have no idea when it's done, so take a look at logs, and when is done use pull_heap_dump"
}

pull_heap_dump() {
  adb pull $heap_dump_location $1
}

https://gist.github.com/logcat/8aeca0ee81af6fb0dc10bb0d58940007