Different execution time

Question

Hello, when i run the bellow code more than one time i am getting different execution time("Total time taken"),
Ex. when i run first time it prints Total time taken 47
second time it prints Total time taken 16
thrid time Total time taken 78 ,why its vary,
Please solve my question
long l = System.currentTimeMillis();
System.out.println(l);
     for(int i=0; i <88; i++){
          System.out.print("Hello ");
     System.out.println("\n"+" Total time taken "+(System.currentTimeMillis() - l));

Answer 1

Its worth noting that the application is IO bound (due to printing to a device/console)
So you are really testing the performance of your IDE/console.
public static void main(String... args) throws IOException {
    int count = 100 * 1000;
    long start = 0;
    for (int i = -count / 10; i < count; i++) {
        if (i == 0)
            start = System.nanoTime();
        System.out.print("Hello ");
    long time = System.nanoTime() - start;
    System.out.printf("%nTotal time taken %,5d micro-seconds per call%n", time / count);
}