*       "safe" edge is created.
 *   <li>If a cycle is detected, an "unsafe" (cyclic) edge is created to represent a potential
 *       deadlock situation, and the appropriate Policy is executed.
 * </ul>
 *
 * <p>Note that detection of potential deadlock does not necessarily indicate that deadlock will
 * happen, as it is possible that higher level application logic prevents the cyclic lock

    assertThat(expected.getCause()).isEqualTo(firstException.getCause());
    // lockA should work after lockB is released.
    lockB.unlock();
    lockA.lock();
  }

  // Tests transitive deadlock detection.
  public void testDeadlock_threeLocks() {
    // Establish an ordering from lockA -> lockB.
    lockA.lock();
    lockB.lock();
    lockB.unlock();
    lockA.unlock();

    assertThat(expected.getCause()).isEqualTo(firstException.getCause());
    // lockA should work after lockB is released.
    lockB.unlock();
    lockA.lock();
  }

  // Tests transitive deadlock detection.
  public void testDeadlock_threeLocks() {
    // Establish an ordering from lockA -> lockB.
    lockA.lock();
    lockB.lock();
    lockB.unlock();
    lockA.unlock();

                }
                assertTrue(hasNonZero, "Each array should have a signature");
            }
        }

        @Test
        @DisplayName("Should handle high concurrency without deadlock")
        void testHighConcurrencyNoDeadlock() throws InterruptedException {
            int threadCount = 100;
            int operationsPerThread = 50;

  // threadpool, so that we avoid the possibility of running the runner_ in the
  // threadpool of GPU event mgr, as that can trigger more callbacks to be
  // scheduled on that same threadpool, causing a deadlock in cases where the
  // caller of event_mgr->ThenExecute() blocks on the completion of the callback
  // (as in the case of ConstOp kernel creation on GPU, which involves copying a
  // CPU tensor to GPU).

  }

  public void testCustomScheduler_deadlock() throws InterruptedException, BrokenBarrierException {
    CyclicBarrier inGetNextSchedule = new CyclicBarrier(2);
    // This will flakily deadlock, so run it multiple times to increase the flake likelihood
    for (int i = 0; i < 1000; i++) {
      Service service =
          new AbstractScheduledService() {
            @Override

  }

  public void testCustomScheduler_deadlock() throws InterruptedException, BrokenBarrierException {
    CyclicBarrier inGetNextSchedule = new CyclicBarrier(2);
    // This will flakily deadlock, so run it multiple times to increase the flake likelihood
    for (int i = 0; i < 1000; i++) {
      Service service =
          new AbstractScheduledService() {
            @Override

   * This covers a bug where if a listener was installed that would stop the manager if any service
   * fails and something failed during startup before service.start was called on all the services,
   * then awaitStopped would deadlock due to an IllegalStateException that was thrown when trying to
   * stop the timer(!).
   */
  public void testFailStart_stopOthers() throws TimeoutException {
    Service a = new FailStartService();

   * This covers a bug where if a listener was installed that would stop the manager if any service
   * fails and something failed during startup before service.start was called on all the services,
   * then awaitStopped would deadlock due to an IllegalStateException that was thrown when trying to
   * stop the timer(!).
   */
  public void testFailStart_stopOthers() throws TimeoutException {
    Service a = new FailStartService();

  /**
   * Returns the stripes that correspond to the passed objects, in ascending (as per {@link
   * #getAt(int)}) order. Thus, threads that use the stripes in the order returned by this method
   * are guaranteed to not deadlock each other.
   *
   * <p>It should be noted that using a {@code Striped<L>} with relatively few stripes, and {@code
   * bulkGet(keys)} with a relative large number of keys can cause an excessive number of shared