Java VisualVM 内存抽样和CPU抽样不可用，求大佬告知如何解决，感谢！！

[aoi.tsukasa]

public class StackAllocation {
public static void main(String[] args) {
long start = System.currentTimeMillis();

for (int i = 0; i < 10000000; i++) {
alloc();
}
// 查看执行时间
long end = System.currentTimeMillis();
System.out.println("花费的时间为： " + (end - start) + " ms");
// 为了方便查看堆内存中对象个数，线程sleep
try {
Thread.sleep(1000000);
} catch (InterruptedException e1) {
e1.printStackTrace();
}
}

private static void alloc() {
User user = new User();//未发生逃逸
}

static class User {

}
}