@Startup
@Singleton
public class TaskScheduler {

    @Resource
    ManagedScheduledExecutorService executorService;

    @PostConstruct
    public void init() {
        executorService.scheduleAtFixedRate(this::task, 0, 5, TimeUnit.SECONDS);
    }

    public void task() {
        System.out.println("long running task:" + LocalTime.now());
    }
}

12:44:12,715 ERROR [org.jboss.as.ee] (EE-ManagedScheduledExecutorService-default-Thread-3) WFLYEE0110: Failed to run scheduled task: java.lang.IllegalStateException: WFLYEE0111: Cannot run scheduled task my.Task$$Lambda$1041/0x000000080240a040@5ee966ec as container is suspended
	at org.jboss.as.ee@17.0.1.Final//org.jboss.as.ee.concurrent.ControlPointUtils$ControlledScheduledRunnable.run(ControlPointUtils.java:164)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
	at java.base/java.util.concurrent.FutureTask.runAndReset(FutureTask.java:305)
	at org.glassfish.javax.enterprise.concurrent//org.glassfish.enterprise.concurrent.internal.ManagedScheduledThreadPoolExecutor$ManagedScheduledFutureTask.access$201(ManagedScheduledThreadPoolExecutor.java:383)
	at org.glassfish.javax.enterprise.concurrent//org.glassfish.enterprise.concurrent.internal.ManagedScheduledThreadPoolExecutor$ManagedScheduledFutureTask.run(ManagedScheduledThreadPoolExecutor.java:534)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:835)
	at org.glassfish.javax.enterprise.concurrent//org.glassfish.enterprise.concurrent.ManagedThreadFactoryImpl$ManagedThread.run(ManagedThreadFactoryImpl.java:250)