|
public static float getProcessCpuRate()
{
float totalCpuTime1 = getTotalCpuTime();
float processCpuTime1 = getAppCpuTime();
try
{
Thread.sleep(360);
}
catch (Exception e)
{
}
float totalCpuTime2 = getTotalCpuTime();
float processCpuTime2 = getAppCpuTime();
float cpuRate = 100 * (processCpuTime2 - processCpuTime1)
/ (totalCpuTime2 - totalCpuTime1);
return cpuRate;
}
public static long getTotalCpuTime()
{ // 获取系统总CPU使用时间
String[] cpuInfos = null;
try
{
BufferedReader reader = new BufferedReader(new InputStreamReader(
new FileInputStream("/proc/stat")), 1000);
String load = reader.readLine();
reader.close();
cpuInfos = load.split(" ");
}
catch (IOException ex)
{
ex.printStackTrace();
}
long totalCpu = Long.parseLong(cpuInfos[2])
+ Long.parseLong(cpuInfos[3]) + Long.parseLong(cpuInfos[4])
+ Long.parseLong(cpuInfos[6]) + Long.parseLong(cpuInfos[5])
+ Long.parseLong(cpuInfos[7]) + Long.parseLong(cpuInfos[8]);
return totalCpu;
}
public static long getAppCpuTime()
{ // 获取应用占用的CPU时间
String[] cpuInfos = null;
try
{
int pid = android.os.Process.myPid();
BufferedReader reader = new BufferedReader(new InputStreamReader(
new FileInputStream("/proc/" + pid + "/stat")), 1000);
String load = reader.readLine();
reader.close();
cpuInfos = load.split(" ");
}
catch (IOException ex)
{
ex.printStackTrace();
}
long appCpuTime = Long.parseLong(cpuInfos[13])
+ Long.parseLong(cpuInfos[14]) + Long.parseLong(cpuInfos[15])
+ Long.parseLong(cpuInfos[16]);
return appCpuTime;
}
|
计算某个时间段内AppCpuTime与TotalCpuTime的变化，然后按照比例换算成该应用的Cpu使用率。
Android系统本省也有一个类是用来显示Cpu使用率的：
android/system/frameworks/base/packages/SystemUI/src/com/android/systemui/LoadAverageService.java
阅读源码发现也是读取/proc目录下的文件来计算Cpu使用率
另外一种方式Runtime.getRuntime().exec("top -d 1 -n 1")，但是每次都获取到的cpu使用率为0，找不到原因http://www.m2catalyst.com/tutorial-finding-cpu-usage-for-individual-android-apps/
来源：oschina
链接：https://my.oschina.net/u/1429862/blog/223371
