Identify high CPU consumed thread for Java app
- by Vincent Ma
Following java code to emulate busy and Idle thread and start it.
import java.util.concurrent.*;import java.lang.*;
public class ThreadTest { public static void main(String[] args) { new Thread(new Idle(), "Idle").start(); new Thread(new Busy(), "Busy").start(); }}class Idle implements Runnable { @Override public void run() { try { TimeUnit.HOURS.sleep(1); } catch (InterruptedException e) { } }}class Busy implements Runnable { @Override public void run() { while(true) { "Test".matches("T.*"); } }}
Using Processor Explorer to get this busy java processor and get Thread id it cost lots of CPU
see the following screenshot:
Cover to 4044 to Hexadecimal is oxfcc.
Using VistulVM to dump thread and get that thread.
see the following screenshot
In Linux you can use top -H to get Thread information.
That it!
Any question let me know. Thanks
