*
 * <p>{@code RuntimeException}s thrown by tasks are simply logged and the executor keeps trucking.
 * If an {@code Error} is thrown, the error will propagate and execution will stop until it is
 * restarted by a call to {@link #execute}.
 */
@J2ktIncompatible
@GwtIncompatible
final class SequentialExecutor implements Executor {
  private static final LazyLogger log = new LazyLogger(SequentialExecutor.class);

@J2ktIncompatible
@GwtIncompatible
public interface Service {
  /**
   * If the service state is {@link State#NEW}, this initiates service startup and returns
   * immediately. A stopped service may not be restarted.
   *
   * @return this
   * @throws IllegalStateException if the service is not {@link State#NEW}
   * @since 15.0
   */
  @CanIgnoreReturnValue
  Service startAsync();

* Handled internally by a cloud provider as part of their services
* Others...

I'll give you more concrete examples in the next chapters.

## Restarts { #restarts }

Similar to making sure your application is run on startup, you probably also want to make sure it is **restarted** after failures.

### We Make Mistakes { #we-make-mistakes }

@J2ktIncompatible
@GwtIncompatible
public interface Service {
  /**
   * If the service state is {@link State#NEW}, this initiates service startup and returns
   * immediately. A stopped service may not be restarted.
   *
   * @return this
   * @throws IllegalStateException if the service is not {@link State#NEW}
   * @since 15.0
   */
  @CanIgnoreReturnValue
  Service startAsync();

the containers will be restarted by Kubelet (see details in [#23104](https://github.com/kubernetes/kubernetes/issues/23104)).

#### Docker Known Issues

##### 1.9.1

  * Listing containers can be slow at times which will affect kubelet performance.
More information [here](https://github.com/docker/docker/issues/17720)
  * Docker daemon restarts can fail. Docker checkpoints have to deleted between

// 'freeze' is 'false' would resume all S3 API calls again.
// NOTE: once a tenant is frozen either two things needs to
// happen before resuming normal operations.
//   - Server needs to be restarted 'mc admin service restart'
//   - 'freeze' should be set to 'false' for this call
//     to resume normal operations.
func (sys *NotificationSys) ServiceFreeze(ctx context.Context, freeze bool) []NotificationPeerErr {

## Running on Startup and Restarts { #running-on-startup-and-restarts }

There is normally another tool in charge of **starting and running** your container.

It could be **Docker** directly, **Docker Compose**, **Kubernetes**, a **cloud service**, etc.

// cmdType - Represents different service subcomands like status, stop
// and restart.
type cmdType int

const (
	restartCmd cmdType = iota
	stopCmd
)

// toServiceSignal - Helper function that translates a given cmdType
// value to its corresponding serviceSignal value.
func (c cmdType) toServiceSignal() serviceSignal {
	switch c {
	case restartCmd:
		return serviceRestart
	case stopCmd:
		return serviceStop

[19515] [INFO] Booting worker with pid: 19515
[19511] [INFO] Started server process [19511]
[19511] [INFO] Waiting for application startup.
[19511] [INFO] Application startup complete.
[19513] [INFO] Started server process [19513]
[19513] [INFO] Waiting for application startup.
[19513] [INFO] Application startup complete.
[19514] [INFO] Started server process [19514]
[19514] [INFO] Waiting for application startup.

	objAPI := newObjectLayerFn()
	if objAPI == nil {
		return errServerNotInitialized
	}

	started := tracker.Started
	if started.IsZero() || started.Equal(timeSentinel) {
		healingLogIf(ctx, fmt.Errorf("unexpected tracker healing start time found: %v", started))
		started = time.Time{}
	}

	// Final tracer update before quitting
	defer func() {
		tracker.setObject("")