I want to get the overall CPU usage on Android, similar to what Windows' Task Manager does. I can parse the output of the top
program included in Android, but if there is a API call that does the same thing, it would be better.
Any pointers?
ATTENTION: This answer is old and does NOT work on newer versions of Android due to enhanced security mechanisms.
For complete CPU usage (not for each process) you can use:
/**
*
* @return integer Array with 4 elements: user, system, idle and other cpu
* usage in percentage.
*/
private int[] getCpuUsageStatistic() {
String tempString = executeTop();
tempString = tempString.replaceAll(",", "");
tempString = tempString.replaceAll("User", "");
tempString = tempString.replaceAll("System", "");
tempString = tempString.replaceAll("IOW", "");
tempString = tempString.replaceAll("IRQ", "");
tempString = tempString.replaceAll("%", "");
for (int i = 0; i < 10; i++) {
tempString = tempString.replaceAll(" ", " ");
}
tempString = tempString.trim();
String[] myString = tempString.split(" ");
int[] cpuUsageAsInt = new int[myString.length];
for (int i = 0; i < myString.length; i++) {
myString[i] = myString[i].trim();
cpuUsageAsInt[i] = Integer.parseInt(myString[i]);
}
return cpuUsageAsInt;
}
private String executeTop() {
java.lang.Process p = null;
BufferedReader in = null;
String returnString = null;
try {
p = Runtime.getRuntime().exec("top -n 1");
in = new BufferedReader(new InputStreamReader(p.getInputStream()));
while (returnString == null || returnString.contentEquals("")) {
returnString = in.readLine();
}
} catch (IOException e) {
Log.e("executeTop", "error in getting first line of top");
e.printStackTrace();
} finally {
try {
in.close();
p.destroy();
} catch (IOException e) {
Log.e("executeTop",
"error in closing and destroying top process");
e.printStackTrace();
}
}
return returnString;
}
Have fun with it :)