Performance considerations for Thread.sleep() and schedulerExecutorService.scheduleWithFixedDelay

Question

I am trying to write a daemon thread for polling which will poll every "3" seconds. I've seen 3 approaches. I am not sure which one to go for ? I want to know the performance considerations. Which one could be consistant and will take smaller memory chunk ?

Approach 1 : Using the TimerTask ( Not planning to use this )

    new Timer().scheduleAtFixedRate(task, firstTime, period)

Approach 2 : Using ScheduledExecutorService

Approach 3 : Using Thread.sleep() ....

If I boil down to code its something like this :

Approach #2

public class Test {

    static TimerTask timerTask = new TimerTask() {
        @Override
        public void run() {
              // Do polling & Other business logic
            System.out.println("=="+new Date());
        }
    };

    public static void main(String[] args) {

        ScheduledExecutorService scheduler = Executors
                .newSingleThreadScheduledExecutor();
        scheduler.scheduleWithFixedDelay(timerTask, 0, 3, TimeUnit.SECONDS);

    }
}

For the

Approach #3

public class Test {

    static Runnable task = new Runnable() {
        @Override
        public void run() {
            while (true) {
                try {
                // Do polling & Other business logic
                    System.out.println("**"+new Date());
                    Thread.sleep(3000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    };

    public static void main(String[] args) {
        new Thread(task).start();
    }

}

According to my understanding threadpools are kind of heavy objects compared to normal threads. I want to know what are the pros and cons of using either of these approaches ?

Thanks in advance.

Regards, JE

Answer 1

Keep pushing the msg at regular interval may cause overflow at the endpoint if for some reason endpoint become slow Hence I think you should consider throttling of pushing request as well instead of blindly pushing the requests at regular interval. Based on all such requirements I think you can opt for ExecutorService, Instead of TimerTask or low level thread approach. Example of ExecutorService http://tutorials.jenkov.com/java-util-concurrent/executorservice.html