Javadoc
The number of threads used by ContainerLifecycleEventPreloader. The ContainerLifecycleEventPreloader allows observer methods for container lifecycle
events to be resolved upfront while the deployment is waiting for classloader or reflection API.
ContainerLifecycleEventPreloader has its own thread pool whose size is configured by this property.
If set to 0, ContainerLifecycleEventPreloader is not installed.
If not specified, the value is set to Math.max(1, Runtime.getRuntime().availableProcessors() - 1)).