Measuring Activity start time using method tracing inaccurate?

Question

My activity (that uses camera) starts quite slowly, according to Logcat:

08-21 21:51:56.672: I/ActivityManager(488): Displayed com.blabla/.activities.TakePhotoActivity: +1s472ms

So I decided to use method profiling to see where the problem is (this is where the slow Activity is started):

public void onClick(View v) {
    Debug.startMethodTracing();
    Intent intent = new Intent(getApplicationContext(), TakePhotoActivity.class);
    startActivity(intent);
    overridePendingTransition(R.anim.enter_from_right, R.anim.exit_to_left);
}

and in onResume in TakePhotoActivity I call:

protected void onResume() {
    super.onResume();
    cameraView.onResume();
    Debug.stopMethodTracing();
}

But, to my surprise, Traceview shows only 260ms of method calls, so I'm losing over 1 second somewhere!

How do I find out what is happening during this time?

This certainly comes from the call to `Camera.open()`. To be sure, take a systrace trace from DDMS — Simon Marquis, Aug 21 '14 at 21:03
I guess Debug.startMethodTracing("Sample") and Debug.stopMethodTracing() takes some time, so that ActivityManager is displaying you more seconds. — Abduaziz Kayumov, Sep 28 '18 at 14:33

score 1 · Accepted Answer · answered Sep 01 '14 at 04:16

1

Here is a good tutorial about how to use trace view on Android application.Just run it and check which all sub methods are causing the time lose.It has a nice visual representation of time usage.

answered Sep 01 '14 at 04:16

vrnithinkumar

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Measuring Activity start time using method tracing inaccurate?

1 Answers1