Usando una imagen de contenedor pre-hecha es muy fácil **combinar** y utilizar diferentes herramientas. Por ejemplo, para probar una nueva base de datos. En la mayoría de los casos, puedes usar las **imágenes oficiales**, y simplemente configurarlas con variables de entorno.

De esta manera, en muchos casos puedes aprender sobre contenedores y Docker y reutilizar ese conocimiento con muchas herramientas y componentes diferentes.

- Sometimes, the scheduler incorrectly placed a pod in the "unschedulable" queue instead of the "backoff" queue. This happened when some plugin previously declared the pod as "unschedulable" and then in a later attempt encounters some other error. Scheduling of that pod then got delayed by up to five minutes, after which periodic flushing moved the pod back into the "active" queue. ([#120334](https://github.com/kubernetes/kubernetes/pull/120334), [@pohly](https://github.com/pohly))...

    startNs = queue.taskRunner.backend.nanoTime()
    log(task, queue, "starting")
  }

  var completedNormally = false
  try {
    val result = block()
    completedNormally = true
    return result
  } finally {
    if (loggingEnabled) {
      val elapsedNs = queue.taskRunner.backend.nanoTime() - startNs
      if (completedNormally) {
        log(task, queue, "finished run in ${formatDuration(elapsedNs)}")

    ListenerCallQueue<Object> queue = new ListenerCallQueue<>();
    queue.addListener(listener, directExecutor());

    Multiset<Object> counters = ConcurrentHashMultiset.create();
    queue.enqueue(incrementingEvent(counters, listener, 1));
    queue.enqueue(THROWING_EVENT);
    queue.enqueue(incrementingEvent(counters, listener, 2));
    queue.enqueue(THROWING_EVENT);
    queue.enqueue(incrementingEvent(counters, listener, 3));

    ListenerCallQueue<Object> queue = new ListenerCallQueue<>();
    queue.addListener(listener, directExecutor());

    Multiset<Object> counters = ConcurrentHashMultiset.create();
    queue.enqueue(incrementingEvent(counters, listener, 1));
    queue.enqueue(THROWING_EVENT);
    queue.enqueue(incrementingEvent(counters, listener, 2));
    queue.enqueue(THROWING_EVENT);
    queue.enqueue(incrementingEvent(counters, listener, 3));

    assertEquals(6, queue.size());
    assertEquals(8, queue.capacity());
    checkUnbounded(queue);
    checkNatural(queue);
  }

  public void testCreation_maximumSize_withContents() {
    MinMaxPriorityQueue<Integer> queue =
        rawtypeToWildcard(MinMaxPriorityQueue.maximumSize(42)).create(NUMBERS);
    assertEquals(6, queue.size());
    assertEquals(11, queue.capacity());
    assertEquals(42, queue.maximumSize);

  @Param({"100", "10000"})
  private int size;

  @Param private HeapType heap;

  private Queue<Integer> queue;

  private final Random random = new Random();

  @BeforeExperiment
  void setUp() {
    queue = heap.create(comparator.get());
    for (int i = 0; i < size; i++) {
      queue.add(random.nextInt());
    }
  }

  @Benchmark
  void pollAndAdd(int reps) {

  }

  @Test fun taskFailsWithUncheckedException() {
    queue.schedule("task", TimeUnit.MILLISECONDS.toNanos(100)) {
      log.put("failing task running")
      throw RuntimeException("boom!")
    }

    queue.schedule("task", TimeUnit.MILLISECONDS.toNanos(200)) {
      log.put("normal task running")
      return@schedule -1L
    }

    queue.idleLatch().await(500, TimeUnit.MILLISECONDS)

    private final BlockingQueue<String> queue;

    EnableWrites(BlockingQueue<String> queue, long tMinus) {
      super(tMinus);
      assertFalse(queue.isEmpty());
      assertFalse(queue.offer("shouldBeRejected"));
      this.queue = queue;
    }

    @Override
    protected void doAction() {
      assertNotNull(queue.remove());
    }
  }

    return QueueTestSuiteBuilder.using(
            new TestStringQueueGenerator() {
              @Override
              public Queue<String> create(String[] elements) {
                Queue<String> queue = new LinkedList<>(MinimalCollection.of(elements));
                return Collections.checkedQueue(queue, String.class);
              }
            })
        .named("checkedQueue/LinkedList")
        .withFeatures(