问多线程不平衡Java

EN

class TestThread extends Thread {   
    @Override
    public void run() {
        while (true) {
            System.out.println("Run thread "+this.getId());
            try {
                Thread.sleep(10000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

for (int i = 0; i < 100; i++) {
    TestThread tt = new TestThread();
    tt.run();
}

Run thread 8
Run thread 8
Run thread 8
Run thread 8
...