android: how to get memory usage (ram) of a given PID programically

Question

i want to log ram usage of a given application at a given time rate. i wrote the code to get the full memory value used but do not know how to get the memory usage of a given PI

Answer 1

ActivityManager localActivityManager = (ActivityManager)getSystemService(Context.ACTIVITY_SERVICE); // use Context.ACTIVITY_SERVICE not the literal "activity"
List<ActivityManager.RunningAppProcessInfo> procsInfo = localActivityManager.getRunningAppProcesses();

int[] pids = new int[procsInfo.size()];
for (int i = 0; i < procsInfo.size(); i++) {
    ActivityManager.RunningAppProcessInfo info = procsInfo.get(i);
    pids[i] = info.pid;
}

Debug.MemoryInfo[] procsMemInfo = localActivityManager.getProcessMemoryInfo(pids);
// now walk the procsMemInfo array

If you schedule a recurring timer to periodically re-query for running pids and query for memory info you can use timestamps to compute the memory usage over time.