I was trying to simulate a deadlock situation that I was going to record with Java Flight Recorder and inspect with Java Mission Control.
By some reason blocked threads are not marked as blocked under Threads section and Automated Analysis in Java Mission Control section also does not report deadlock situation
Meanwhile, collected thread dumps clearly indicate that thread are blocked and 1 deadlock is found
public class ExternalDeadLock {
private static Lock lock1 = new ReentrantLock();
private static Lock lock2 = new ReentrantLock();
static Runnable task1 = () -> {
while(true) {
try {
lock1.lock();
sleep();
lock2.lock();
System.out.println("task 1 still running");
} finally {
lock1.unlock();
lock2.unlock();
}
}
};
static Runnable task2 = () -> {
while(true) {
try {
lock2.lock();
sleep();
lock1.lock();
System.out.println("task 2 still running");
} finally {
lock1.unlock();
lock2.unlock();
}
}
};
private static void sleep() {
try {
Thread.sleep(100);
}
catch (InterruptedException e) {
e.printStackTrace();
}
}
public static void main(String[] args) throws InterruptedException {
Scanner scanner = new Scanner(System.in);
System.out.println("Press enter to initiate dead lock");
scanner.nextLine();
ExecutorService executor = Executors.newCachedThreadPool();
executor.submit(task1);
executor.submit(task2);
executor.awaitTermination(10000, TimeUnit.DAYS);
}
}
I am using standard "profiling" metrics preset with all default settings.
I am trying to understand where I am doing wrong that makes deadlock situation so unobvious in Java Mission Control
